Video Tutorials : Moved language to a server side concept

This CL
1 - Adds language struct to the proto consisting of name, native text,
  and locale.
2 - VideoTutorialService will still store the preferred locale in a
  pref which will be used as a key when iterating through the
  supporting languages.
3 - Removes the checked in strings for languages

TODO : Change server side proto

Bug: 1132161
Change-Id: I1483903e0615714aa790b6af1fbfaa4c6637c802
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2429979
Commit-Queue: Shakti Sahu <shaktisahu@chromium.org>
Reviewed-by: Min Qin <qinmin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#811131}

chrome/android/expectations/lint-suppressions.xml

@@ -246,16 +246,6 @@ Still reading?
     <ignore regexp="The resource `R.string.video_tutorials_change_language` appears to be unused"/>
     <ignore regexp="The resource `R.string.video_tutorials_iph_tap_here_to_start` appears to be unused"/>
     <ignore regexp="The resource `R.string.video_tutorials_iph_tap_voice_icon_to_start` appears to be unused"/>
-    <ignore regexp="The resource `R.string.video_tutorials_language_english` appears to be unused"/>
-    <ignore regexp="The resource `R.string.video_tutorials_language_hindi` appears to be unused"/>
-    <ignore regexp="The resource `R.string.video_tutorials_language_kannada` appears to be unused"/>
-    <ignore regexp="The resource `R.string.video_tutorials_language_tamil` appears to be unused"/>
-    <ignore regexp="The resource `R.string.video_tutorials_language_telugu` appears to be unused"/>
-    <ignore regexp="The resource `R.string.video_tutorials_language_english_native_text` appears to be unused"/>
-    <ignore regexp="The resource `R.string.video_tutorials_language_hindi_native_text` appears to be unused"/>
-    <ignore regexp="The resource `R.string.video_tutorials_language_kannada_native_text` appears to be unused"/>
-    <ignore regexp="The resource `R.string.video_tutorials_language_tamil_native_text` appears to be unused"/>
-    <ignore regexp="The resource `R.string.video_tutorials_language_telugu_native_text` appears to be unused"/>
     <ignore regexp="The resource `R.string.video_tutorials_language_picker_title` appears to be unused"/>
     <ignore regexp="The resource `R.string.video_tutorials_learn_chrome` appears to be unused"/>
     <ignore regexp="The resource `R.string.video_tutorials_popular_videos` appears to be unused"/>

chrome/browser/resources/video_tutorials/video_player.js

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import {$} from 'chrome://resources/js/util.m.js';
+import {$} from 'chrome-untrusted://resources/js/util.m.js';
 
 function onDocumentLoaded() {
   // Find out the video, image, and caption urls from the url params.

chrome/browser/ui/android/strings/android_chrome_strings.grd

@@ -2759,36 +2759,6 @@ In Incognito, your activity might still be visible to websites that you visit, y
       <message name="IDS_VIDEO_TUTORIALS_IPH_TAP_VOICE_ICON_TO_START" desc="In-product help bubble text prompting user to start typing on the search box or tap on the microphone icon to start a voice search.">
         Type here or tap the voice icon to start
       </message>
-      <message name="IDS_VIDEO_TUTORIALS_LANGUAGE_ENGLISH" desc="Language option presented to the user in the video tutorial language picker. Shown in the system language script.">
-        English
-      </message>
-      <message name="IDS_VIDEO_TUTORIALS_LANGUAGE_ENGLISH_NATIVE_TEXT" desc="Language option presented to the user in the video tutorial language picker. Shown in the native script." translateable="false">
-        English
-      </message>
-      <message name="IDS_VIDEO_TUTORIALS_LANGUAGE_HINDI" desc="Language option presented to the user in the video tutorial language picker. Shown in the system language script.">
-        Hindi
-      </message>
-      <message name="IDS_VIDEO_TUTORIALS_LANGUAGE_HINDI_NATIVE_TEXT" desc="Language option presented to the user in the video tutorial language picker. Shown in the native script." translateable="false">
-        हिन्दी
-      </message>
-      <message name="IDS_VIDEO_TUTORIALS_LANGUAGE_TAMIL" desc="Language option presented to the user in the video tutorial language picker. Shown in the system language script.">
-        Tamil
-      </message>
-      <message name="IDS_VIDEO_TUTORIALS_LANGUAGE_TAMIL_NATIVE_TEXT" desc="Language option presented to the user in the video tutorial language picker. Shown in the native script." translateable="false">
-        தமிழ்
-      </message>
-      <message name="IDS_VIDEO_TUTORIALS_LANGUAGE_TELUGU" desc="Language option presented to the user in the video tutorial language picker. Shown in the system language script.">
-        Telugu
-      </message>
-      <message name="IDS_VIDEO_TUTORIALS_LANGUAGE_TELUGU_NATIVE_TEXT" desc="Language option presented to the user in the video tutorial language picker. Shown in the native script." translateable="false">
-        తెలుగు
-      </message>
-      <message name="IDS_VIDEO_TUTORIALS_LANGUAGE_KANNADA" desc="Language option presented to the user in the video tutorial language picker. Shown in the system language script.">
-        Kannada
-      </message>
-      <message name="IDS_VIDEO_TUTORIALS_LANGUAGE_KANNADA_NATIVE_TEXT" desc="Language option presented to the user in the video tutorial language picker. Shown in the native script." translateable="false">
-        ಕನ್ನಡ
-      </message>
 
       <!-- Toolbar button strings -->
       <message name="IDS_OPEN_TABS" desc="Text for button to enter the tab switcher and show tabs that are open on this device">

chrome/browser/ui/android/strings/android_chrome_strings_grd/IDS_VIDEO_TUTORIALS_LANGUAGE_ENGLISH.png.sha1

-88c3f1e3fe5bf1044e437bd0ee554c3e44bc12f9
\ No newline at end of file

chrome/browser/ui/android/strings/android_chrome_strings_grd/IDS_VIDEO_TUTORIALS_LANGUAGE_HINDI.png.sha1

-88c3f1e3fe5bf1044e437bd0ee554c3e44bc12f9

chrome/browser/ui/android/strings/android_chrome_strings_grd/IDS_VIDEO_TUTORIALS_LANGUAGE_KANNADA.png.sha1

-88c3f1e3fe5bf1044e437bd0ee554c3e44bc12f9

chrome/browser/ui/android/strings/android_chrome_strings_grd/IDS_VIDEO_TUTORIALS_LANGUAGE_TAMIL.png.sha1

-88c3f1e3fe5bf1044e437bd0ee554c3e44bc12f9

chrome/browser/ui/android/strings/android_chrome_strings_grd/IDS_VIDEO_TUTORIALS_LANGUAGE_TELUGU.png.sha1

-88c3f1e3fe5bf1044e437bd0ee554c3e44bc12f9

chrome/browser/video_tutorials/BUILD.gn

@@ -55,6 +55,7 @@ source_set("factory") {
 if (is_android) {
   android_library("java") {
     sources = [
+      "android/java/src/org/chromium/chrome/browser/video_tutorials/Language.java",
       "android/java/src/org/chromium/chrome/browser/video_tutorials/Tutorial.java",
       "android/java/src/org/chromium/chrome/browser/video_tutorials/VideoTutorialService.java",
       "android/java/src/org/chromium/chrome/browser/video_tutorials/iph/VideoIPHCoordinator.java",

chrome/browser/video_tutorials/android/java/src/org/chromium/chrome/browser/video_tutorials/Language.java

+// Copyright 2020 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.chrome.browser.video_tutorials;
+
+/**
+ * Class encapsulating data needed to show a language on the language selection UI.
+ */
+public class Language {
+    /** The locale associated with the language. */
+    public final String locale;
+
+    /** The name of the language. */
+    public final String name;
+
+    /** The name of the language in native text. */
+    public final String nativeName;
+
+    /** Constructor */
+    public Language(String locale, String name, String nativeName) {
+        this.locale = locale;
+        this.name = name;
+        this.nativeName = nativeName;
+    }
+}

chrome/browser/video_tutorials/android/java/src/org/chromium/chrome/browser/video_tutorials/VideoTutorialService.java

@@ -26,7 +26,7 @@ public interface VideoTutorialService {
     /**
      * Called to get the list of supported languages.
      */
-    List<String> getSupportedLanguages();
+    List<Language> getSupportedLanguages();
 
     /**
      * @return The user's language of choice for watching the video tutorials.

chrome/browser/video_tutorials/internal/BUILD.gn

@@ -70,7 +70,6 @@ if (is_android) {
       "android/java/src/org/chromium/chrome/browser/video_tutorials/languages/LanguagePickerCoordinator.java",
       "android/java/src/org/chromium/chrome/browser/video_tutorials/languages/LanguagePickerProperties.java",
       "android/java/src/org/chromium/chrome/browser/video_tutorials/languages/LanguagePickerView.java",
-      "android/java/src/org/chromium/chrome/browser/video_tutorials/languages/LanguageUtils.java",
       "android/java/src/org/chromium/chrome/browser/video_tutorials/player/VideoPlayerCoordinatorImpl.java",
       "android/java/src/org/chromium/chrome/browser/video_tutorials/player/VideoPlayerMediator.java",
       "android/java/src/org/chromium/chrome/browser/video_tutorials/player/VideoPlayerProperties.java",

chrome/browser/video_tutorials/internal/android/java/src/org/chromium/chrome/browser/video_tutorials/bridges/TutorialConversionBridge.java

@@ -8,6 +8,7 @@ import androidx.annotation.Nullable;
 
 import org.chromium.base.annotations.CalledByNative;
 import org.chromium.base.annotations.JNINamespace;
+import org.chromium.chrome.browser.video_tutorials.Language;
 import org.chromium.chrome.browser.video_tutorials.Tutorial;
 
 import java.util.ArrayList;
@@ -19,7 +20,20 @@ import java.util.List;
 @JNINamespace("video_tutorials")
 public class TutorialConversionBridge {
     @CalledByNative
-    private static List<Tutorial> createList() {
+    private static List<Language> createLanguageList() {
+        return new ArrayList<>();
+    }
+
+    @CalledByNative
+    private static Language createLanguageAndMaybeAddToList(
+            @Nullable List<Language> list, String locale, String name, String nativeName) {
+        Language language = new Language(locale, name, nativeName);
+        if (list != null) list.add(language);
+        return language;
+    }
+
+    @CalledByNative
+    private static List<Tutorial> createTutorialList() {
         return new ArrayList<>();
     }
 

chrome/browser/video_tutorials/internal/android/java/src/org/chromium/chrome/browser/video_tutorials/bridges/VideoTutorialServiceBridge.java

@@ -9,6 +9,7 @@ import org.chromium.base.annotations.CalledByNative;
 import org.chromium.base.annotations.JNINamespace;
 import org.chromium.base.annotations.NativeMethods;
 import org.chromium.chrome.browser.video_tutorials.FeatureType;
+import org.chromium.chrome.browser.video_tutorials.Language;
 import org.chromium.chrome.browser.video_tutorials.Tutorial;
 import org.chromium.chrome.browser.video_tutorials.VideoTutorialService;
 
@@ -45,9 +46,9 @@ public class VideoTutorialServiceBridge implements VideoTutorialService {
     }
 
     @Override
-    public List<String> getSupportedLanguages() {
+    public List<Language> getSupportedLanguages() {
         if (mNativeVideoTutorialServiceBridge == 0) return null;
-        return VideoTutorialServiceBridgeJni.get().getSupportedLocales(
+        return VideoTutorialServiceBridgeJni.get().getSupportedLanguages(
                 mNativeVideoTutorialServiceBridge, this);
     }
 
@@ -76,7 +77,7 @@ public class VideoTutorialServiceBridge implements VideoTutorialService {
                 Callback<List<Tutorial>> callback);
         void getTutorial(long nativeVideoTutorialServiceBridge, VideoTutorialServiceBridge caller,
                 int feature, Callback<Tutorial> callback);
-        List<String> getSupportedLocales(
+        List<Language> getSupportedLanguages(
                 long nativeVideoTutorialServiceBridge, VideoTutorialServiceBridge caller);
         String getPreferredLocale(
                 long nativeVideoTutorialServiceBridge, VideoTutorialServiceBridge caller);

chrome/browser/video_tutorials/internal/android/java/src/org/chromium/chrome/browser/video_tutorials/languages/LanguagePickerCoordinator.java

@@ -9,6 +9,7 @@ import android.content.res.Resources;
 import android.text.TextUtils;
 import android.view.View;
 
+import org.chromium.chrome.browser.video_tutorials.Language;
 import org.chromium.chrome.browser.video_tutorials.VideoTutorialService;
 import org.chromium.ui.modelutil.MVCListAdapter.ListItem;
 import org.chromium.ui.modelutil.MVCListAdapter.ModelList;
@@ -61,9 +62,9 @@ public class LanguagePickerCoordinator {
         populateList(mVideoTutorialService.getSupportedLanguages());
     }
 
-    private void populateList(List<String> supportedLocales) {
+    private void populateList(List<Language> supportedLanguages) {
         List<ListItem> listItems = new ArrayList<>();
-        for (String locale : supportedLocales) {
+        for (Language locale : supportedLanguages) {
             ListItem listItem = new ListItem(
                     LanguageItemProperties.ITEM_VIEW_TYPE, buildListItemModelFromLocale(locale));
             listItems.add(listItem);
@@ -71,16 +72,15 @@ public class LanguagePickerCoordinator {
         mListModel.set(listItems);
     }
 
-    private PropertyModel buildListItemModelFromLocale(String locale) {
+    private PropertyModel buildListItemModelFromLocale(Language language) {
         Resources resources = mContext.getResources();
         String preferredLocale = mVideoTutorialService.getPreferredLocale();
         return new PropertyModel.Builder(LanguageItemProperties.ALL_KEYS)
-                .with(LanguageItemProperties.LOCALE, locale)
-                .with(LanguageItemProperties.NAME,
-                        LanguageUtils.getLanguageForLocale(resources, locale))
-                .with(LanguageItemProperties.NATIVE_NAME,
-                        LanguageUtils.getLanguageForLocaleInNativeText(resources, locale))
-                .with(LanguageItemProperties.IS_SELECTED, TextUtils.equals(locale, preferredLocale))
+                .with(LanguageItemProperties.LOCALE, language.locale)
+                .with(LanguageItemProperties.NAME, language.name)
+                .with(LanguageItemProperties.NATIVE_NAME, language.nativeName)
+                .with(LanguageItemProperties.IS_SELECTED,
+                        TextUtils.equals(language.locale, preferredLocale))
                 .with(LanguageItemProperties.SELECTION_CALLBACK, this::onLanguageSelected)
                 .build();
     }

chrome/browser/video_tutorials/internal/android/java/src/org/chromium/chrome/browser/video_tutorials/languages/LanguageUtils.java

-// Copyright 2020 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-package org.chromium.chrome.browser.video_tutorials.languages;
-
-import android.content.res.Resources;
-import android.text.TextUtils;
-
-import org.chromium.chrome.browser.video_tutorials.R;
-
-/**
- * Utility class that provides methods for converting between locales and languages.
- */
-public class LanguageUtils {
-    private static final String LOCALE_HINDI = "hi-IN";
-    private static final String LOCALE_TAMIL = "ta-IN";
-    private static final String LOCALE_TELUGU = "te-IN";
-    private static final String LOCALE_KANNADA = "kn-IN";
-    private static final String LOCALE_ENGLISH = "en-IN";
-
-    /** For a given locale, returns the name of the language in the native text. */
-    public static String getLanguageForLocaleInNativeText(Resources resources, String locale) {
-        if (TextUtils.equals(locale, LOCALE_HINDI)) {
-            return resources.getString(R.string.video_tutorials_language_hindi_native_text);
-        } else if (TextUtils.equals(locale, LOCALE_TAMIL)) {
-            return resources.getString(R.string.video_tutorials_language_tamil_native_text);
-        } else if (TextUtils.equals(locale, LOCALE_TELUGU)) {
-            return resources.getString(R.string.video_tutorials_language_telugu_native_text);
-        } else if (TextUtils.equals(locale, LOCALE_KANNADA)) {
-            return resources.getString(R.string.video_tutorials_language_kannada_native_text);
-        } else if (TextUtils.equals(locale, LOCALE_ENGLISH)) {
-            return resources.getString(R.string.video_tutorials_language_english_native_text);
-        }
-        return null;
-    }
-
-    /** For a given locale, returns the name of the language in the system text. */
-    public static String getLanguageForLocale(Resources resources, String locale) {
-        if (TextUtils.equals(locale, LOCALE_HINDI)) {
-            return resources.getString(R.string.video_tutorials_language_hindi);
-        } else if (TextUtils.equals(locale, LOCALE_TAMIL)) {
-            return resources.getString(R.string.video_tutorials_language_tamil);
-        } else if (TextUtils.equals(locale, LOCALE_TELUGU)) {
-            return resources.getString(R.string.video_tutorials_language_telugu);
-        } else if (TextUtils.equals(locale, LOCALE_KANNADA)) {
-            return resources.getString(R.string.video_tutorials_language_kannada);
-        } else if (TextUtils.equals(locale, LOCALE_ENGLISH)) {
-            return resources.getString(R.string.video_tutorials_language_english);
-        }
-        return null;
-    }
-}

chrome/browser/video_tutorials/internal/android/java/src/org/chromium/chrome/browser/video_tutorials/player/VideoPlayerMediator.java

@@ -5,14 +5,15 @@
 package org.chromium.chrome.browser.video_tutorials.player;
 
 import android.content.Context;
+import android.text.TextUtils;
 
+import org.chromium.chrome.browser.video_tutorials.Language;
 import org.chromium.chrome.browser.video_tutorials.PlaybackStateObserver;
 import org.chromium.chrome.browser.video_tutorials.R;
 import org.chromium.chrome.browser.video_tutorials.Tutorial;
 import org.chromium.chrome.browser.video_tutorials.VideoTutorialService;
 import org.chromium.chrome.browser.video_tutorials.VideoTutorialUtils;
 import org.chromium.chrome.browser.video_tutorials.languages.LanguagePickerCoordinator;
-import org.chromium.chrome.browser.video_tutorials.languages.LanguageUtils;
 import org.chromium.content_public.browser.LoadUrlParams;
 import org.chromium.content_public.browser.WebContents;
 import org.chromium.ui.modelutil.PropertyModel;
@@ -97,11 +98,14 @@ class VideoPlayerMediator implements PlaybackStateObserver.Observer {
     }
 
     private void updateChangeLanguageButtonText() {
-        String language = LanguageUtils.getLanguageForLocale(
-                mContext.getResources(), mVideoTutorialService.getPreferredLocale());
-        String buttonText = mContext.getResources().getString(
-                R.string.video_tutorials_change_language, language == null ? "" : language);
-        mModel.set(VideoPlayerProperties.CHANGE_LANGUAGE_BUTTON_TEXT, buttonText);
+        String locale = mVideoTutorialService.getPreferredLocale();
+        for (Language language : mVideoTutorialService.getSupportedLanguages()) {
+            if (TextUtils.equals(language.locale, locale)) {
+                String buttonText = mContext.getResources().getString(
+                        R.string.video_tutorials_change_language, language.nativeName);
+                mModel.set(VideoPlayerProperties.CHANGE_LANGUAGE_BUTTON_TEXT, buttonText);
+            }
+        }
     }
 
     private void onLanguageSelected() {

chrome/browser/video_tutorials/internal/android/tutorial_conversion_bridge.cc

@@ -16,6 +16,28 @@ namespace video_tutorials {
 using base::android::ConvertUTF8ToJavaString;
 using base::android::ToJavaArrayOfStrings;
 
+ScopedJavaLocalRef<jobject> CreateJavaLanguageAndMaybeAddToList(
+    JNIEnv* env,
+    ScopedJavaLocalRef<jobject> jlist,
+    const Language& language) {
+  return Java_TutorialConversionBridge_createLanguageAndMaybeAddToList(
+      env, jlist, ConvertUTF8ToJavaString(env, language.locale),
+      ConvertUTF8ToJavaString(env, language.name),
+      ConvertUTF8ToJavaString(env, language.native_name));
+}
+
+ScopedJavaLocalRef<jobject> TutorialConversionBridge::CreateJavaLanguages(
+    JNIEnv* env,
+    const std::vector<Language>& languages) {
+  ScopedJavaLocalRef<jobject> jlist =
+      Java_TutorialConversionBridge_createLanguageList(env);
+
+  for (const auto& language : languages)
+    CreateJavaLanguageAndMaybeAddToList(env, jlist, language);
+
+  return jlist;
+}
+
 ScopedJavaLocalRef<jobject> CreateJavaTutorialAndMaybeAddToList(
     JNIEnv* env,
     ScopedJavaLocalRef<jobject> jlist,
@@ -34,7 +56,7 @@ ScopedJavaLocalRef<jobject> TutorialConversionBridge::CreateJavaTutorials(
     JNIEnv* env,
     const std::vector<Tutorial>& tutorials) {
   ScopedJavaLocalRef<jobject> jlist =
-      Java_TutorialConversionBridge_createList(env);
+      Java_TutorialConversionBridge_createTutorialList(env);
 
   for (const auto& tutorial : tutorials)
     CreateJavaTutorialAndMaybeAddToList(env, jlist, tutorial);

chrome/browser/video_tutorials/internal/android/tutorial_conversion_bridge.h

@@ -19,6 +19,10 @@ namespace video_tutorials {
 // and Java.
 class TutorialConversionBridge {
  public:
+  static ScopedJavaLocalRef<jobject> CreateJavaLanguages(
+      JNIEnv* env,
+      const std::vector<Language>& languages);
+
   static ScopedJavaLocalRef<jobject> CreateJavaTutorials(
       JNIEnv* env,
       const std::vector<Tutorial>& tutorials);

chrome/browser/video_tutorials/internal/android/video_tutorial_service_bridge.cc

@@ -90,12 +90,11 @@ void VideoTutorialServiceBridge::GetTutorial(
                      ScopedJavaGlobalRef<jobject>(jcallback)));
 }
 
-ScopedJavaLocalRef<jobject> VideoTutorialServiceBridge::GetSupportedLocales(
+ScopedJavaLocalRef<jobject> VideoTutorialServiceBridge::GetSupportedLanguages(
     JNIEnv* env,
     const JavaParamRef<jobject>& jcaller) {
-  std::vector<std::string> locales =
-      video_tutorial_service_->GetSupportedLocales();
-  return base::android::ToJavaArrayOfStrings(env, locales);
+  return TutorialConversionBridge::CreateJavaLanguages(
+      env, video_tutorial_service_->GetSupportedLanguages());
 }
 
 ScopedJavaLocalRef<jstring> VideoTutorialServiceBridge::GetPreferredLocale(

chrome/browser/video_tutorials/internal/android/video_tutorial_service_bridge.h

@@ -37,7 +37,7 @@ class VideoTutorialServiceBridge : public base::SupportsUserData::Data {
                    const JavaParamRef<jobject>& jcaller,
                    jint j_feature,
                    const JavaParamRef<jobject>& jcallback);
-  ScopedJavaLocalRef<jobject> GetSupportedLocales(
+  ScopedJavaLocalRef<jobject> GetSupportedLanguages(
       JNIEnv* env,
       const JavaParamRef<jobject>& jcaller);
   ScopedJavaLocalRef<jstring> GetPreferredLocale(

chrome/browser/video_tutorials/internal/proto_conversions.cc

@@ -47,6 +47,22 @@ proto::FeatureType FromFeatureType(FeatureType type) {
 
 }  // namespace
 
+void LanguageToProto(Language* language, LanguageProto* proto) {
+  DCHECK(language);
+  DCHECK(proto);
+  proto->set_locale(language->locale);
+  proto->set_name(language->name);
+  proto->set_native_name(language->native_name);
+}
+
+void LanguageFromProto(LanguageProto* proto, Language* language) {
+  DCHECK(language);
+  DCHECK(proto);
+  language->locale = proto->locale();
+  language->name = proto->name();
+  language->native_name = proto->native_name();
+}
+
 void TutorialToProto(Tutorial* tutorial, TutorialProto* proto) {
   DCHECK(tutorial);
   DCHECK(proto);
@@ -74,7 +90,7 @@ void TutorialFromProto(TutorialProto* proto, Tutorial* tutorial) {
 void TutorialGroupToProto(TutorialGroup* group, TutorialGroupProto* proto) {
   DCHECK(group);
   DCHECK(proto);
-  proto->set_locale(group->locale);
+  LanguageToProto(&group->language, proto->mutable_language());
   proto->clear_tutorials();
   for (auto& tutorial : group->tutorials)
     TutorialToProto(&tutorial, proto->add_tutorials());
@@ -83,7 +99,7 @@ void TutorialGroupToProto(TutorialGroup* group, TutorialGroupProto* proto) {
 void TutorialGroupFromProto(TutorialGroupProto* proto, TutorialGroup* group) {
   DCHECK(group);
   DCHECK(proto);
-  group->locale = proto->locale();
+  LanguageFromProto(proto->mutable_language(), &group->language);
   group->tutorials.clear();
   for (auto tutorial_proto : proto->tutorials()) {
     Tutorial tutorial;

chrome/browser/video_tutorials/internal/proto_conversions.h

@@ -10,9 +10,16 @@
 
 namespace video_tutorials {
 
+using LanguageProto = video_tutorials::proto::Language;
 using TutorialProto = video_tutorials::proto::VideoTutorial;
 using TutorialGroupProto = video_tutorials::proto::VideoTutorialGroup;
 
+// Convert in-memory struct Language to proto::Language.
+void LanguageToProto(Language* language, LanguageProto* proto);
+
+// Convert proto::Language to in-memory struct Language.
+void LanguageFromProto(LanguageProto* proto, Language* language);
+
 // Convert in-memory struct Tutorial to proto::VideoTutorial.
 void TutorialToProto(Tutorial* tutorial, TutorialProto* proto);
 

chrome/browser/video_tutorials/internal/store.h

@@ -20,16 +20,16 @@ namespace video_tutorials {
 template <typename T>
 class Store {
  public:
-  using Keys = std::unique_ptr<std::vector<std::string>>;
-  using Entries = std::vector<std::unique_ptr<T>>;
-  using LoadKeysCallback = base::OnceCallback<void(bool, Keys)>;
+  using Entries = std::unique_ptr<std::vector<T>>;
+  using SuccessCallback = base::OnceCallback<void(bool)>;
   using LoadEntriesCallback = base::OnceCallback<void(bool, Entries)>;
   using UpdateCallback = base::OnceCallback<void(bool)>;
 
-  // Initialize the db and load keys into memory.
-  virtual void InitAndLoadKeys(LoadKeysCallback callback) = 0;
+  // Initialize the db and load entries into memory.
+  virtual void Initialize(SuccessCallback callback) = 0;
 
-  // Load entries with the given keys into memory.
+  // Load entries with the given keys into memory. If |keys| is empty, load all
+  // the entries.
   virtual void LoadEntries(const std::vector<std::string>& keys,
                            LoadEntriesCallback callback) = 0;
 

chrome/browser/video_tutorials/internal/tutorial_group.cc

@@ -8,10 +8,10 @@ namespace video_tutorials {
 
 TutorialGroup::TutorialGroup() = default;
 
-TutorialGroup::TutorialGroup(const std::string& locale) : locale(locale) {}
+TutorialGroup::TutorialGroup(const Language& language) : language(language) {}
 
 bool TutorialGroup::operator==(const TutorialGroup& other) const {
-  return locale == other.locale && tutorials == other.tutorials;
+  return language == other.language && tutorials == other.tutorials;
 }
 
 bool TutorialGroup::operator!=(const TutorialGroup& other) const {

chrome/browser/video_tutorials/internal/tutorial_group.h

@@ -12,7 +12,7 @@ namespace video_tutorials {
 // In memory struct of a group of video tutorials with same language .
 struct TutorialGroup {
   TutorialGroup();
-  explicit TutorialGroup(const std::string& locale);
+  explicit TutorialGroup(const Language& language);
   ~TutorialGroup();
 
   bool operator==(const TutorialGroup& other) const;
@@ -22,7 +22,7 @@ struct TutorialGroup {
   TutorialGroup& operator=(const TutorialGroup& other);
 
   // Language of this group.
-  std::string locale;
+  Language language;
 
   // A list of tutorials.
   std::vector<Tutorial> tutorials;

chrome/browser/video_tutorials/internal/tutorial_group_unittest.cc

@@ -10,7 +10,9 @@ namespace video_tutorials {
 namespace {
 
 void ResetTutorialGroup(TutorialGroup* group) {
-  *group = TutorialGroup("en");
+  Language language;
+  language.locale = "en";
+  *group = TutorialGroup(language);
   group->tutorials.resize(3, Tutorial());
   group->tutorials.front().feature = FeatureType::kDownload;
   group->tutorials.back().feature = FeatureType::kSearch;
@@ -24,7 +26,7 @@ TEST(VideoTutorialGroupTest, CopyAndCompareOperators) {
 
   EXPECT_EQ(lhs, rhs);
 
-  rhs.locale = "jp";
+  rhs.language.locale = "jp";
   EXPECT_NE(lhs, rhs);
   ResetTutorialGroup(&rhs);
 

chrome/browser/video_tutorials/internal/tutorial_manager.h

@@ -17,16 +17,12 @@ class TutorialManager {
   using SuccessCallback = base::OnceCallback<void(bool)>;
   using GetTutorialsCallback = base::OnceCallback<void(std::vector<Tutorial>)>;
 
-  // Initialization method that reads the database and loads video tutorials
-  // into in-memory.
-  virtual void Init(SuccessCallback callback) = 0;
-
   // Loads video tutorials. Must be called again if the locale was changed by
   // the user.
   virtual void GetTutorials(GetTutorialsCallback callback) = 0;
 
-  // Returns a list of locales for which video tutorials are available.
-  virtual const std::vector<std::string>& GetSupportedLocales() = 0;
+  // Returns a list of languages for which video tutorials are available.
+  virtual const std::vector<Language>& GetSupportedLanguages() = 0;
 
   // Returns the preferred locale for the video tutorials.
   virtual std::string GetPreferredLocale() = 0;
@@ -38,7 +34,7 @@ class TutorialManager {
 
   // Saves a fresh set of video tutorials into database. Called after a network
   // fetch.
-  virtual void SaveGroups(std::vector<std::unique_ptr<TutorialGroup>> groups,
+  virtual void SaveGroups(std::unique_ptr<std::vector<TutorialGroup>> groups,
                           SuccessCallback callback) = 0;
 
   virtual ~TutorialManager() = default;

chrome/browser/video_tutorials/internal/tutorial_manager_impl.cc

@@ -16,20 +16,29 @@ namespace video_tutorials {
 
 TutorialManagerImpl::TutorialManagerImpl(std::unique_ptr<TutorialStore> store,
                                          PrefService* prefs)
-    : store_(std::move(store)), prefs_(prefs) {}
+    : store_(std::move(store)), prefs_(prefs) {
+  Initialize();
+}
 
 TutorialManagerImpl::~TutorialManagerImpl() = default;
 
-void TutorialManagerImpl::Init(SuccessCallback callback) {
-  store_->InitAndLoadKeys(base::BindOnce(&TutorialManagerImpl::OnInitCompleted,
-                                         weak_ptr_factory_.GetWeakPtr(),
-                                         std::move(callback)));
+void TutorialManagerImpl::Initialize() {
+  store_->Initialize(base::BindOnce(&TutorialManagerImpl::OnInitCompleted,
+                                    weak_ptr_factory_.GetWeakPtr()));
 }
 
 void TutorialManagerImpl::GetTutorials(GetTutorialsCallback callback) {
+  if (!init_success_.has_value()) {
+    MaybeCacheApiCall(base::BindOnce(&TutorialManagerImpl::GetTutorials,
+                                     weak_ptr_factory_.GetWeakPtr(),
+                                     std::move(callback)));
+    return;
+  }
+
   // Find the data from cache.
   std::string locale = GetPreferredLocale();
-  if (tutorial_group_ && tutorial_group_->locale == locale) {
+  if (tutorial_group_.has_value() &&
+      tutorial_group_->language.locale == locale) {
     std::move(callback).Run(tutorial_group_->tutorials);
     return;
   }
@@ -42,8 +51,8 @@ void TutorialManagerImpl::GetTutorials(GetTutorialsCallback callback) {
                      weak_ptr_factory_.GetWeakPtr(), std::move(callback)));
 }
 
-const std::vector<std::string>& TutorialManagerImpl::GetSupportedLocales() {
-  return supported_locales_;
+const std::vector<Language>& TutorialManagerImpl::GetSupportedLanguages() {
+  return supported_languages_;
 }
 
 std::string TutorialManagerImpl::GetPreferredLocale() {
@@ -56,56 +65,84 @@ void TutorialManagerImpl::SetPreferredLocale(const std::string& locale) {
   prefs_->SetString(kPreferredLocaleKey, locale);
 }
 
-void TutorialManagerImpl::OnInitCompleted(
-    SuccessCallback callback,
-    bool success,
-    std::unique_ptr<std::vector<std::string>> supported_locales) {
-  if (!success) {
-    std::move(callback).Run(success);
+void TutorialManagerImpl::OnInitCompleted(bool success) {
+  if (!success)
     return;
+
+  store_->LoadEntries({},
+                      base::BindOnce(&TutorialManagerImpl::OnInitialDataLoaded,
+                                     weak_ptr_factory_.GetWeakPtr()));
+}
+
+void TutorialManagerImpl::OnInitialDataLoaded(
+    bool success,
+    std::unique_ptr<std::vector<TutorialGroup>> all_groups) {
+  if (all_groups) {
+    for (auto& tutorial_group : *all_groups) {
+      supported_languages_.emplace_back(tutorial_group.language);
+    }
   }
 
-  if (supported_locales)
-    supported_locales_ = *supported_locales.get();
+  DCHECK(!init_success_.has_value());
+  init_success_ = success;
 
-  std::move(callback).Run(true);
+  // Flush all cached calls in FIFO sequence.
+  while (!cached_api_calls_.empty()) {
+    auto api_call = std::move(cached_api_calls_.front());
+    cached_api_calls_.pop_front();
+    std::move(api_call).Run();
+  }
 }
 
 void TutorialManagerImpl::OnTutorialsLoaded(
     GetTutorialsCallback callback,
     bool success,
-    std::vector<std::unique_ptr<TutorialGroup>> loaded_group) {
-  if (!success || loaded_group.empty()) {
+    std::unique_ptr<std::vector<TutorialGroup>> loaded_groups) {
+  if (!success || !loaded_groups || loaded_groups->empty()) {
     std::move(callback).Run(std::vector<Tutorial>());
     return;
   }
 
+  if (!init_success_.has_value()) {
+    MaybeCacheApiCall(base::BindOnce(
+        &TutorialManagerImpl::OnTutorialsLoaded, weak_ptr_factory_.GetWeakPtr(),
+        std::move(callback), success, std::move(loaded_groups)));
+    return;
+  }
+
   // We are loading tutorials only for the preferred locale.
-  DCHECK(loaded_group.size() == 1u);
-  tutorial_group_ = std::move(loaded_group.front());
+  DCHECK(loaded_groups->size() == 1u);
+  tutorial_group_ = loaded_groups->front();
   std::move(callback).Run(tutorial_group_->tutorials);
 }
 
 void TutorialManagerImpl::SaveGroups(
-    std::vector<std::unique_ptr<TutorialGroup>> groups,
+    std::unique_ptr<std::vector<TutorialGroup>> groups,
     SuccessCallback callback) {
   std::vector<std::string> new_locales;
   std::vector<std::pair<std::string, TutorialGroup>> key_entry_pairs;
-  for (auto& group : groups) {
-    new_locales.emplace_back(group->locale);
-    key_entry_pairs.emplace_back(std::make_pair(group->locale, *group));
+  for (auto& group : *groups.get()) {
+    new_locales.emplace_back(group.language.locale);
+    key_entry_pairs.emplace_back(std::make_pair(group.language.locale, group));
   }
 
-  // Remove the locales that don't exist in the new data.
+  // Remove the languages that don't exist in the new data.
+  // TODO(shaktisahu): Maybe completely nuke the DB and save new data.
   std::vector<std::string> keys_to_delete;
-  for (auto& old_locale : supported_locales_) {
-    if (std::find(new_locales.begin(), new_locales.end(), old_locale) ==
-        new_locales.end()) {
-      keys_to_delete.emplace_back(old_locale);
+  for (auto& old_language : supported_languages_) {
+    if (std::find(new_locales.begin(), new_locales.end(),
+                  old_language.locale) == new_locales.end()) {
+      keys_to_delete.emplace_back(old_language.locale);
     }
   }
 
   store_->UpdateAll(key_entry_pairs, keys_to_delete, std::move(callback));
 }
 
+void TutorialManagerImpl::MaybeCacheApiCall(base::OnceClosure api_call) {
+  DCHECK(!init_success_.has_value())
+      << "Only cache API calls before initialization.";
+  cached_api_calls_.emplace_back(std::move(api_call));
+}
+
 }  // namespace video_tutorials

chrome/browser/video_tutorials/internal/tutorial_manager_impl.h

@@ -7,11 +7,13 @@
 
 #include "chrome/browser/video_tutorials/internal/tutorial_manager.h"
 
+#include <deque>
 #include <memory>
 #include <string>
 #include <vector>
 
 #include "base/memory/weak_ptr.h"
+#include "base/optional.h"
 #include "chrome/browser/video_tutorials/internal/store.h"
 
 class PrefService;
@@ -26,32 +28,38 @@ class TutorialManagerImpl : public TutorialManager {
 
  private:
   // TutorialManager implementation.
-  void Init(SuccessCallback callback) override;
   void GetTutorials(GetTutorialsCallback callback) override;
-  const std::vector<std::string>& GetSupportedLocales() override;
+  const std::vector<Language>& GetSupportedLanguages() override;
   std::string GetPreferredLocale() override;
   void SetPreferredLocale(const std::string& locale) override;
-  void SaveGroups(std::vector<std::unique_ptr<TutorialGroup>> groups,
+  void SaveGroups(std::unique_ptr<std::vector<TutorialGroup>> groups,
                   SuccessCallback callback) override;
 
-  void OnInitCompleted(
-      SuccessCallback callback,
+  void Initialize();
+  void OnInitCompleted(bool success);
+  void OnInitialDataLoaded(
       bool success,
-      std::unique_ptr<std::vector<std::string>> supported_locales);
-
+      std::unique_ptr<std::vector<TutorialGroup>> all_groups);
+  void MaybeCacheApiCall(base::OnceClosure api_call);
   void OnTutorialsLoaded(
       GetTutorialsCallback callback,
       bool success,
-      std::vector<std::unique_ptr<TutorialGroup>> loaded_group);
+      std::unique_ptr<std::vector<TutorialGroup>> loaded_groups);
 
   std::unique_ptr<TutorialStore> store_;
   PrefService* prefs_;
 
-  // List of locales for which we have tutorials.
-  std::vector<std::string> supported_locales_;
+  // List of languages for which we have tutorials.
+  std::vector<Language> supported_languages_;
 
   // We only keep the tutorials for the preferred locale.
-  std::unique_ptr<TutorialGroup> tutorial_group_;
+  base::Optional<TutorialGroup> tutorial_group_;
+
+  // The initialization result of the database.
+  base::Optional<bool> init_success_;
+
+  // Caches the API calls in case initialization is not completed.
+  std::deque<base::OnceClosure> cached_api_calls_;
 
   base::WeakPtrFactory<TutorialManagerImpl> weak_ptr_factory_{this};
 };

chrome/browser/video_tutorials/internal/tutorial_manager_impl_unittest.cc

@@ -10,6 +10,7 @@
 #include "base/bind.h"
 #include "base/run_loop.h"
 #include "base/test/task_environment.h"
+#include "chrome/browser/video_tutorials/prefs.h"
 #include "components/prefs/testing_pref_service.h"
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
@@ -26,7 +27,7 @@ std::vector<TutorialGroup> CreateSampleGroups(
   std::vector<TutorialGroup> groups;
   for (const auto& locale : locales) {
     TutorialGroup group;
-    group.locale = locale;
+    group.language.locale = locale;
     group.tutorials.emplace_back(Tutorial());
     group.tutorials.emplace_back(Tutorial());
     groups.emplace_back(group);
@@ -35,11 +36,11 @@ std::vector<TutorialGroup> CreateSampleGroups(
   return groups;
 }
 
-std::vector<std::unique_ptr<TutorialGroup>> CreateSampleFetchData(
+std::unique_ptr<std::vector<TutorialGroup>> CreateSampleFetchData(
     const std::vector<std::string>& locales) {
-  std::vector<std::unique_ptr<TutorialGroup>> groups;
+  auto groups = std::make_unique<std::vector<TutorialGroup>>();
   for (const auto& group : CreateSampleGroups(locales)) {
-    groups.emplace_back(std::make_unique<TutorialGroup>(group));
+    groups->emplace_back(group);
   }
 
   return groups;
@@ -50,29 +51,30 @@ class TestStore : public Store<TutorialGroup> {
   TestStore() = default;
   ~TestStore() override = default;
 
-  void InitAndLoadKeys(LoadKeysCallback callback) override {
-    std::vector<std::string> keys;
-    for (const TutorialGroup& group : groups_)
-      keys.emplace_back(group.locale);
-
-    std::move(callback).Run(true,
-                            std::make_unique<std::vector<std::string>>(keys));
+  void Initialize(SuccessCallback callback) override {
+    std::move(callback).Run(true);
   }
 
   void LoadEntries(const std::vector<std::string>& keys,
                    LoadEntriesCallback callback) override {
-    std::vector<std::unique_ptr<TutorialGroup>> entries;
+    auto entries = std::make_unique<std::vector<TutorialGroup>>();
     for (const TutorialGroup& group : groups_) {
-      if (group.locale != locale_)
-        continue;
-      entries.emplace_back(std::make_unique<TutorialGroup>(group));
+      if (keys.empty()) {
+        entries->emplace_back(group);
+      } else {
+        for (auto& key : keys) {
+          if (key == group.language.locale) {
+            entries->emplace_back(group);
+          }
+        }
+      }
     }
 
     std::move(callback).Run(true, std::move(entries));
   }
 
-  void Initialize(const std::string& locale,
-                  const std::vector<TutorialGroup>& groups) {
+  void InitStoreData(const std::string& locale,
+                     const std::vector<TutorialGroup>& groups) {
     locale_ = locale;
     groups_ = groups;
   }
@@ -101,8 +103,9 @@ class TutorialManagerTest : public testing::Test {
   TutorialManagerTest(const TutorialManagerTest& other) = delete;
   TutorialManagerTest& operator=(const TutorialManagerTest& other) = delete;
 
-  void SetUp() override {
-    auto tutorial_store = std::make_unique<StrictMock<TestStore>>();
+  void SetUp() override { video_tutorials::RegisterPrefs(prefs_.registry()); }
+
+  void CreateTutorialManager(std::unique_ptr<TestStore> tutorial_store) {
     tutorial_store_ = tutorial_store.get();
     manager_ = std::make_unique<TutorialManagerImpl>(std::move(tutorial_store),
                                                      &prefs_);
@@ -110,33 +113,25 @@ class TutorialManagerTest : public testing::Test {
 
   // Run GetTutorials call from manager_, compare the |expected| to the actual
   // returned tutorials.
-  void GetTutorials(std::vector<Tutorial> expected) {
+  void GetTutorials() {
     base::RunLoop loop;
-    manager()->GetTutorials(base::BindOnce(
-        &TutorialManagerTest::OnGetTutorials, base::Unretained(this),
-        loop.QuitClosure(), std::move(expected)));
+    manager()->GetTutorials(base::BindOnce(&TutorialManagerTest::OnGetTutorials,
+                                           base::Unretained(this),
+                                           loop.QuitClosure()));
     loop.Run();
   }
 
   void OnGetTutorials(base::RepeatingClosure closure,
-                      std::vector<Tutorial> expected,
                       std::vector<Tutorial> tutorials) {
-    EXPECT_TRUE(expected.size() == tutorials.size());
+    last_results_ = tutorials;
     std::move(closure).Run();
   }
 
-  void Init() {
-    base::RunLoop loop;
-    manager()->Init(base::BindOnce(&TutorialManagerTest::OnComplete,
-                                   base::Unretained(this), loop.QuitClosure()));
-    loop.Run();
-  }
-
   void OnComplete(base::RepeatingClosure closure, bool success) {
     std::move(closure).Run();
   }
 
-  void SaveGroups(std::vector<std::unique_ptr<TutorialGroup>> groups) {
+  void SaveGroups(std::unique_ptr<std::vector<TutorialGroup>> groups) {
     base::RunLoop loop;
     manager()->SaveGroups(
         std::move(groups),
@@ -148,35 +143,45 @@ class TutorialManagerTest : public testing::Test {
  protected:
   TutorialManager* manager() { return manager_.get(); }
   TestStore* tutorial_store() { return tutorial_store_; }
+  std::vector<Tutorial> last_results() { return last_results_; }
 
  private:
   base::test::TaskEnvironment task_environment_;
   TestingPrefServiceSimple prefs_;
   std::unique_ptr<TutorialManager> manager_;
   TestStore* tutorial_store_;
+  std::vector<Tutorial> last_results_;
 };
 
 TEST_F(TutorialManagerTest, InitAndGetTutorials) {
   auto groups = CreateSampleGroups({"hi", "kn"});
-  tutorial_store()->Initialize("hi", groups);
-  Init();
-
-  auto locales = manager()->GetSupportedLocales();
-  EXPECT_EQ(locales.size(), 2u);
-  GetTutorials(groups[0].tutorials);
+  auto tutorial_store = std::make_unique<StrictMock<TestStore>>();
+  tutorial_store->InitStoreData("hi", groups);
+  CreateTutorialManager(std::move(tutorial_store));
+
+  auto languages = manager()->GetSupportedLanguages();
+  EXPECT_EQ(languages.size(), 2u);
+  GetTutorials();
+  EXPECT_EQ(last_results().size(), 2u);
 }
 
 TEST_F(TutorialManagerTest, SaveNewData) {
   auto groups = CreateSampleGroups({"hi", "kn"});
-  tutorial_store()->Initialize("hi", groups);
-  Init();
+  auto tutorial_store = std::make_unique<StrictMock<TestStore>>();
+  tutorial_store->InitStoreData("hi", groups);
+  CreateTutorialManager(std::move(tutorial_store));
 
-  auto locales = manager()->GetSupportedLocales();
-  EXPECT_EQ(locales.size(), 2u);
-  GetTutorials(groups[0].tutorials);
+  auto languages = manager()->GetSupportedLanguages();
+  EXPECT_EQ(languages.size(), 2u);
+  GetTutorials();
+  EXPECT_EQ(last_results().size(), groups[0].tutorials.size());
 
   auto new_groups = CreateSampleFetchData({"hi", "tl", "ar"});
+  auto new_group = new_groups->at(0);
   SaveGroups(std::move(new_groups));
+  manager()->SetPreferredLocale("ar");
+  GetTutorials();
+  EXPECT_EQ(last_results().size(), new_group.tutorials.size());
 }
 
 }  // namespace

chrome/browser/video_tutorials/internal/tutorial_service_impl.cc

@@ -63,8 +63,8 @@ void TutorialServiceImpl::OnFetchFinished(
   // TODO(shaktisahu): Save tutorials to the database.
 }
 
-std::vector<std::string> TutorialServiceImpl::GetSupportedLocales() {
-  return tutorial_manager_->GetSupportedLocales();
+const std::vector<Language>& TutorialServiceImpl::GetSupportedLanguages() {
+  return tutorial_manager_->GetSupportedLanguages();
 }
 
 std::string TutorialServiceImpl::GetPreferredLocale() {

chrome/browser/video_tutorials/internal/tutorial_service_impl.h

@@ -25,7 +25,7 @@ class TutorialServiceImpl : public VideoTutorialService {
   void GetTutorials(MultipleItemCallback callback) override;
   void GetTutorial(FeatureType feature_type,
                    SingleItemCallback callback) override;
-  std::vector<std::string> GetSupportedLocales() override;
+  const std::vector<Language>& GetSupportedLanguages() override;
   std::string GetPreferredLocale() override;
   void SetPreferredLocale(const std::string& locale) override;
 

chrome/browser/video_tutorials/internal/tutorial_store.cc

@@ -6,6 +6,7 @@
 
 #include <utility>
 
+#include "base/logging.h"
 #include "base/stl_util.h"
 
 namespace leveldb_proto {
@@ -28,7 +29,7 @@ TutorialStore::TutorialStore(TutorialProtoDb db) : db_(std::move(db)) {}
 
 TutorialStore::~TutorialStore() = default;
 
-void TutorialStore::InitAndLoadKeys(LoadKeysCallback callback) {
+void TutorialStore::Initialize(SuccessCallback callback) {
   db_->Init(base::BindOnce(&TutorialStore::OnDbInitialized,
                            weak_ptr_factory_.GetWeakPtr(),
                            std::move(callback)));
@@ -36,14 +37,19 @@ void TutorialStore::InitAndLoadKeys(LoadKeysCallback callback) {
 
 void TutorialStore::LoadEntries(const std::vector<std::string>& keys,
                                 LoadEntriesCallback callback) {
+  if (keys.empty()) {
+    // Load all entries.
+    db_->LoadEntries(std::move(callback));
+    return;
+  }
+
   db_->LoadEntriesWithFilter(
       base::BindRepeating(
           [](const std::vector<std::string>& key_dict, const std::string& key) {
             return base::Contains(key_dict, key);
           },
           keys),
-      base::BindOnce(&TutorialStore::OnEntriesLoaded,
-                     weak_ptr_factory_.GetWeakPtr(), std::move(callback)));
+      std::move(callback));
 }
 
 void TutorialStore::UpdateAll(
@@ -62,36 +68,9 @@ void TutorialStore::UpdateAll(
                      std::move(callback));
 }
 
-void TutorialStore::OnDbInitialized(LoadKeysCallback callback,
+void TutorialStore::OnDbInitialized(SuccessCallback callback,
                                     leveldb_proto::Enums::InitStatus status) {
-  if (status != leveldb_proto::Enums::InitStatus::kOK) {
-    std::move(callback).Run(false, Keys());
-    return;
-  }
-
-  db_->LoadKeys(base::BindOnce(&TutorialStore::OnKeysLoaded,
-                               weak_ptr_factory_.GetWeakPtr(),
-                               std::move(callback)));
-}
-
-void TutorialStore::OnKeysLoaded(LoadKeysCallback callback,
-                                 bool success,
-                                 std::unique_ptr<KeyVector> keys) {
-  std::move(callback).Run(success, success ? std::move(keys) : Keys());
-}
-
-void TutorialStore::OnEntriesLoaded(
-    LoadEntriesCallback callback,
-    bool success,
-    std::unique_ptr<std::vector<TutorialGroup>> loaded_entries) {
-  if (!success || !loaded_entries) {
-    std::move(callback).Run(success, Entries());
-    return;
-  }
-  Entries entries;
-  for (auto& loaded_entry : *loaded_entries)
-    entries.emplace_back(std::make_unique<TutorialGroup>(loaded_entry));
-  std::move(callback).Run(true, std::move(entries));
+  std::move(callback).Run(status == leveldb_proto::Enums::InitStatus::kOK);
 }
 
 }  // namespace video_tutorials

chrome/browser/video_tutorials/internal/tutorial_store.h

@@ -47,7 +47,7 @@ class TutorialStore : public Store<TutorialGroup> {
   using EntryVector = std::vector<TutorialGroup>;
 
   // Store<TutorialGroup> implementation.
-  void InitAndLoadKeys(LoadKeysCallback callback) override;
+  void Initialize(SuccessCallback callback) override;
   void LoadEntries(const std::vector<std::string>& keys,
                    LoadEntriesCallback callback) override;
   void UpdateAll(
@@ -56,20 +56,9 @@ class TutorialStore : public Store<TutorialGroup> {
       UpdateCallback callback) override;
 
   // Called when db is initialized.
-  void OnDbInitialized(LoadKeysCallback callback,
+  void OnDbInitialized(SuccessCallback callback,
                        leveldb_proto::Enums::InitStatus status);
 
-  // Called when keys are loaded after initialization.
-  void OnKeysLoaded(LoadKeysCallback callback,
-                    bool success,
-                    std::unique_ptr<std::vector<std::string>> loaded_keys);
-
-  // Called when entries are loaded from db.
-  void OnEntriesLoaded(
-      LoadEntriesCallback callback,
-      bool success,
-      std::unique_ptr<std::vector<TutorialGroup>> loaded_entries);
-
   TutorialProtoDb db_;
 
   base::WeakPtrFactory<TutorialStore> weak_ptr_factory_{this};

chrome/browser/video_tutorials/internal/tutorial_store_unittest.cc

@@ -9,6 +9,7 @@
 #include <string>
 #include <utility>
 
+#include "base/run_loop.h"
 #include "base/test/task_environment.h"
 #include "chrome/browser/video_tutorials/test/test_utils.h"
 #include "components/leveldb_proto/public/proto_database.h"
@@ -26,46 +27,43 @@ class TutorialStoreTest : public testing::Test {
   using EntriesMap = std::map<std::string, std::unique_ptr<TutorialGroup>>;
   using ProtoMap = std::map<std::string, TutorialGroupProto>;
   using KeysAndEntries = std::map<std::string, TutorialGroup>;
-  using TestEntries = std::vector<TutorialGroup>;
-  using TestKeys = std::vector<std::string>;
 
-  TutorialStoreTest() : load_result_(false), db_(nullptr) {}
+  TutorialStoreTest() : db_(nullptr) {}
   ~TutorialStoreTest() override = default;
 
   TutorialStoreTest(const TutorialStoreTest& other) = delete;
   TutorialStoreTest& operator=(const TutorialStoreTest& other) = delete;
 
  protected:
-  void Init(TestEntries input, InitStatus status) {
+  void Init(std::vector<TutorialGroup> input,
+            InitStatus status,
+            bool expected_success) {
     CreateTestDbEntries(std::move(input));
     auto db = std::make_unique<FakeDB<TutorialGroupProto, TutorialGroup>>(
         &db_entries_);
     db_ = db.get();
     store_ = std::make_unique<TutorialStore>(std::move(db));
-    store_->InitAndLoadKeys(base::BindOnce(&TutorialStoreTest::OnKeysLoaded,
-                                           base::Unretained(this)));
+    store_->Initialize(base::BindOnce(&TutorialStoreTest::OnInitCompleted,
+                                      base::Unretained(this),
+                                      expected_success));
     db_->InitStatusCallback(status);
   }
 
-  void OnKeysLoaded(bool success,
-                    std::unique_ptr<std::vector<std::string>> loaded_keys) {
-    load_result_ = success;
-    loaded_keys_.clear();
-    if (success && loaded_keys)
-      loaded_keys_ = *loaded_keys;
+  void OnInitCompleted(bool expected_success, bool success) {
+    EXPECT_EQ(expected_success, success);
   }
 
-  void CreateTestDbEntries(TestEntries input) {
+  void CreateTestDbEntries(std::vector<TutorialGroup> input) {
     for (auto& entry : input) {
       TutorialGroupProto proto;
       TutorialGroupToProto(&entry, &proto);
-      db_entries_.emplace(entry.locale, proto);
+      db_entries_.emplace(entry.language.locale, proto);
     }
   }
 
-  void VerifyLoadEntries(const TestKeys& keys,
-                         bool expected_success,
-                         TestEntries expected_entries) {
+  void LoadEntriesAndVerify(const std::vector<std::string>& keys,
+                            bool expected_success,
+                            std::vector<TutorialGroup> expected_entries) {
     store_->LoadEntries(keys,
                         base::BindOnce(&TutorialStoreTest::OnEntriesLoaded,
                                        base::Unretained(this), expected_success,
@@ -75,14 +73,14 @@ class TutorialStoreTest : public testing::Test {
 
   void OnEntriesLoaded(
       bool expected_success,
-      TestEntries expected_entries,
+      std::vector<TutorialGroup> expected_entries,
       bool success,
-      std::vector<std::unique_ptr<TutorialGroup>> loaded_entries) {
+      std::unique_ptr<std::vector<TutorialGroup>> loaded_entries) {
     EXPECT_EQ(expected_success, success);
-    EXPECT_EQ(loaded_entries.size(), expected_entries.size());
-    TestEntries actual_loaded_entries;
-    for (auto& loaded_entry : loaded_entries) {
-      actual_loaded_entries.emplace_back(*loaded_entry.get());
+    EXPECT_EQ(loaded_entries->size(), expected_entries.size());
+    std::vector<TutorialGroup> actual_loaded_entries;
+    for (auto& loaded_entry : *loaded_entries.get()) {
+      actual_loaded_entries.emplace_back(loaded_entry);
     }
     EXPECT_EQ(expected_entries, actual_loaded_entries);
   }
@@ -109,18 +107,14 @@ class TutorialStoreTest : public testing::Test {
     }
   }
 
-  bool load_result() const { return load_result_; }
   const EntriesMap& loaded_keys_and_entries() const {
     return loaded_keys_and_entries_;
   }
-  const std::vector<std::string>& loaded_keys() const { return loaded_keys_; }
   FakeDB<TutorialGroupProto, TutorialGroup>* db() { return db_; }
   Store<TutorialGroup>* store() { return store_.get(); }
 
  private:
   base::test::TaskEnvironment task_environment_;
-  bool load_result_{false};
-  TestKeys loaded_keys_;
   EntriesMap loaded_keys_and_entries_;
   ProtoMap db_entries_;
   FakeDB<TutorialGroupProto, TutorialGroup>* db_{nullptr};
@@ -128,62 +122,63 @@ class TutorialStoreTest : public testing::Test {
 };
 
 // Test loading keys from a non-empty database in initialization successfully.
-TEST_F(TutorialStoreTest, LoadedKeysSuccess) {
-  auto test_data = TestEntries();
+TEST_F(TutorialStoreTest, InitSuccess) {
   TutorialGroup test_group;
   test::BuildTestGroup(&test_group);
-  std::string locale = test_group.locale;
+  std::vector<TutorialGroup> test_data;
   test_data.emplace_back(std::move(test_group));
-  Init(std::move(test_data), InitStatus::kOK);
-  db()->LoadKeysCallback(true);
-  EXPECT_EQ(load_result(), true);
-  EXPECT_EQ(loaded_keys().size(), 1u);
-  EXPECT_EQ(loaded_keys().front(), locale);
+
+  Init(std::move(test_data), InitStatus::kOK, true /* expected */);
 }
 
-// Test loading keys from a non-empty database failed.
-TEST_F(TutorialStoreTest, LoadKeysFailed) {
-  auto test_data = TestEntries();
+// Test loading all entries from a non-empty database in initialization
+// successfully.
+TEST_F(TutorialStoreTest, LoadAllEntries) {
   TutorialGroup test_group;
   test::BuildTestGroup(&test_group);
-  std::string locale = test_group.locale;
+  std::vector<TutorialGroup> test_data;
   test_data.emplace_back(std::move(test_group));
-  Init(std::move(test_data), InitStatus::kOK);
-  db()->LoadKeysCallback(false);
-  EXPECT_EQ(load_result(), false);
-  EXPECT_TRUE(loaded_keys().empty());
+  auto expected_test_data = test_data;
+
+  Init(std::move(test_data), InitStatus::kOK, true /* expected */);
+  LoadEntriesAndVerify(std::vector<std::string>(), true, expected_test_data);
 }
 
-// Test loading entries with loaded keys successfully.
-TEST_F(TutorialStoreTest, LoadedEntriesSuccess) {
-  auto test_data = TestEntries();
+// Test loading keys from a non-empty database in initialization successfully.
+TEST_F(TutorialStoreTest, LoadSpecificEntries) {
   TutorialGroup test_group;
   test::BuildTestGroup(&test_group);
-  std::string locale = test_group.locale;
+  std::vector<TutorialGroup> test_data;
   test_data.emplace_back(std::move(test_group));
-  Init(test_data, InitStatus::kOK);
-  db()->LoadKeysCallback(true);
-  EXPECT_EQ(load_result(), true);
-  EXPECT_EQ(loaded_keys().size(), 1u);
-  EXPECT_EQ(loaded_keys().front(), locale);
-
-  VerifyLoadEntries(loaded_keys() /*keys*/, true /*expected_success*/,
-                    test_data /*expected_loaded_entries*/);
+  auto expected_test_data = test_data;
+
+  Init(std::move(test_data), InitStatus::kOK, true /* expected */);
+  std::vector<std::string> keys;
+  keys.emplace_back("en");
+  LoadEntriesAndVerify(keys, true, expected_test_data);
+}
+
+TEST_F(TutorialStoreTest, LoadEntryThatDoesntExist) {
+  std::vector<TutorialGroup> test_data;
+  auto expected_test_data = test_data;
+
+  Init(std::move(test_data), InitStatus::kOK, true /* expected */);
+  std::vector<std::string> keys;
+  keys.emplace_back("en");
+  LoadEntriesAndVerify(keys, true, expected_test_data);
 }
 
 // Test adding and updating data successfully.
 TEST_F(TutorialStoreTest, AddAndUpdateDataSuccess) {
-  auto test_data = TestEntries();
-  Init(std::move(test_data), InitStatus::kOK);
-  db()->LoadKeysCallback(true);
-  EXPECT_EQ(load_result(), true);
-  EXPECT_TRUE(loaded_keys().empty());
+  std::vector<TutorialGroup> test_data;
+  Init(std::move(test_data), InitStatus::kOK, true /* expected */);
 
   // Add a group successfully.
   TutorialGroup test_group;
   test::BuildTestGroup(&test_group);
   std::vector<std::pair<std::string, TutorialGroup>> entries_to_save;
-  entries_to_save.emplace_back(std::make_pair(test_group.locale, test_group));
+  entries_to_save.emplace_back(
+      std::make_pair(test_group.language.locale, test_group));
   std::vector<std::string> keys_to_delete;
   store()->UpdateAll(
       entries_to_save, keys_to_delete,
@@ -191,22 +186,19 @@ TEST_F(TutorialStoreTest, AddAndUpdateDataSuccess) {
   db()->UpdateCallback(true);
 
   auto expected = std::make_unique<KeysAndEntries>();
-  expected->emplace(test_group.locale, std::move(test_group));
+  expected->emplace(test_group.language.locale, std::move(test_group));
   VerifyDataInDb(std::move(expected));
 }
 
 // Test deleting entries with keys .
 TEST_F(TutorialStoreTest, Delete) {
-  auto test_data = TestEntries();
   TutorialGroup test_group;
   test::BuildTestGroup(&test_group);
-  std::string locale = test_group.locale;
+  std::string locale = test_group.language.locale;
+  std::vector<TutorialGroup> test_data;
   test_data.emplace_back(std::move(test_group));
-  Init(test_data, InitStatus::kOK);
-  db()->LoadKeysCallback(true);
-  EXPECT_EQ(load_result(), true);
-  EXPECT_EQ(loaded_keys().size(), 1u);
-  EXPECT_EQ(loaded_keys().front(), locale);
+  Init(test_data, InitStatus::kOK, true /* expected */);
+
   std::vector<std::string> keys{locale};
   std::vector<std::pair<std::string, TutorialGroup>> entries_to_save;
 

chrome/browser/video_tutorials/proto/video_tutorials.proto

@@ -18,10 +18,22 @@ enum FeatureType {
   TEST = 9999999;
 }
 
+// Metadata about a language.
+message Language {
+  // The locale associated with the lnaguage.
+  string locale = 1;
+
+  // Name of the language.
+  string name = 2;
+
+  // Name of the language in native text.
+  string native_name = 3;
+}
+
 // A group of video tutorials with same language.
 message VideoTutorialGroup {
-  // Language of the video, in ISO-639-1 two character format. Eg: en, pl, hi.
-  string locale = 1;
+  // Language of the video.
+  Language language = 1;
 
   // A list of video tutorials metadata.
   repeated VideoTutorial tutorials = 2;

chrome/browser/video_tutorials/test/test_utils.cc

@@ -17,7 +17,9 @@ void BuildTestEntry(Tutorial* entry) {
 }
 
 void BuildTestGroup(TutorialGroup* group) {
-  *group = TutorialGroup("en");
+  Language language;
+  language.locale = "en";
+  *group = TutorialGroup(language);
   group->tutorials.clear();
   Tutorial entry1;
   BuildTestEntry(&entry1);

chrome/browser/video_tutorials/tutorial.cc

@@ -6,6 +6,15 @@
 
 namespace video_tutorials {
 
+bool Language::operator==(const Language& other) const {
+  return locale == other.locale && name == other.name &&
+         native_name == other.native_name;
+}
+
+bool Language::operator!=(const Language& other) const {
+  return !(*this == other);
+}
+
 Tutorial::Tutorial() : feature(FeatureType::kInvalid), video_length(0) {}
 
 Tutorial::Tutorial(FeatureType feature,

chrome/browser/video_tutorials/tutorial.h

@@ -23,6 +23,27 @@ enum class FeatureType {
   kMaxValue = kSearch,
 };
 
+// In memory struct representing a language.
+struct Language {
+  Language() = default;
+  ~Language() = default;
+
+  Language(const Language& other) = default;
+  Language& operator=(const Language& other) = default;
+
+  bool operator==(const Language& other) const;
+  bool operator!=(const Language& other) const;
+
+  // The locale associated with the language.
+  std::string locale;
+
+  // The name of the language.
+  std::string name;
+
+  // The name of the language in native text.
+  std::string native_name;
+};
+
 // In memory struct of a video tutorial entry.
 // Represents the metadata required to play a video tutorial.
 struct Tutorial {

chrome/browser/video_tutorials/video_tutorial_service.h

@@ -33,7 +33,7 @@ class VideoTutorialService : public KeyedService,
                            SingleItemCallback callback) = 0;
 
   // Called to retrieve all the supported locales.
-  virtual std::vector<std::string> GetSupportedLocales() = 0;
+  virtual const std::vector<Language>& GetSupportedLanguages() = 0;
 
   // Called to retrieve the preferred locale.
   virtual std::string GetPreferredLocale() = 0;