[Android History] Add a chrome://flags for the Android native history UI

BUG=654071

Review-Url: https://codereview.chromium.org/2580023002
Cr-Commit-Position: refs/heads/master@{#439513}

chrome/android/java/src/org/chromium/chrome/browser/history/HistoryManagerUtils.java

@@ -7,14 +7,12 @@ package org.chromium.chrome.browser.history;
 import android.app.Activity;
 import android.content.Context;
 import android.content.Intent;
-import android.text.TextUtils;
 
-import org.chromium.base.CommandLine;
 import org.chromium.base.ContextUtils;
+import org.chromium.chrome.browser.ChromeFeatureList;
 import org.chromium.chrome.browser.IntentHandler;
 import org.chromium.chrome.browser.UrlConstants;
 import org.chromium.chrome.browser.tab.Tab;
-import org.chromium.components.variations.VariationsAssociatedData;
 import org.chromium.content_public.browser.LoadUrlParams;
 import org.chromium.ui.base.DeviceFormFactor;
 
@@ -22,8 +20,6 @@ import org.chromium.ui.base.DeviceFormFactor;
  * Utility methods for the browsing history manager.
  */
 public class HistoryManagerUtils {
-    private static final String FIELD_TRIAL_NAME = "AndroidHistoryManager";
-    private static final String ENABLE_HISTORY_SWTICH = "enable_android_history_manager";
     private static final Object NATIVE_HISTORY_ENABLED_LOCK = new Object();
     private static Boolean sNativeHistoryEnabled;
 
@@ -33,13 +29,7 @@ public class HistoryManagerUtils {
     public static boolean isAndroidHistoryManagerEnabled() {
         synchronized (NATIVE_HISTORY_ENABLED_LOCK) {
             if (sNativeHistoryEnabled == null) {
-                if (CommandLine.getInstance().hasSwitch(ENABLE_HISTORY_SWTICH)) {
-                    sNativeHistoryEnabled = true;
-                } else {
-                    sNativeHistoryEnabled = TextUtils.equals("true",
-                            VariationsAssociatedData.getVariationParamValue(FIELD_TRIAL_NAME,
-                                    ENABLE_HISTORY_SWTICH));
-                }
+                sNativeHistoryEnabled = ChromeFeatureList.isEnabled("AndroidHistoryManager");
             }
         }
 

chrome/app/generated_resources.grd

@@ -15620,6 +15620,16 @@ read aloud to screenreader users to announce that a completion is available.">
      <message name="IDS_FLAGS_FASTER_LOCATION_RELOAD_DESCRIPTION" desc="Description for the flag to enable faster location.reload()" translateable="false">
       Enable faster location.reload() to use a reload mode that revalidates only main resource forcibly.
     </message>
+
+    <!-- Native Android History chrome://flags strings -->
+    <if expr="is_android">
+      <message name="IDS_NATIVE_ANDROID_HISTORY_MANAGER" desc="Name of the flag that enables the native Android history UI." translateable="false">
+        Native Android History
+      </message>
+      <message name="IDS_NATIVE_ANDROID_HISTORY_MANAGER_DESCRIPTION" desc="Description of the flag that enables the native Android history UI." translateable="false">
+        Show the native Android UI for browsing history.
+      </message>
+    </if>
   </messages>
  </release>
 </grit>

chrome/browser/about_flags.cc

@@ -2142,6 +2142,9 @@ const FeatureEntry kFeatureEntries[] = {
          autofill::kAutofillCreditCardPopupLayout,
          kAutofillCreditCardPopupLayoutFeatureVariations,
          "AutofillCreditCardPopupLayout")},
+     {"native-android-history-manager", IDS_NATIVE_ANDROID_HISTORY_MANAGER,
+      IDS_NATIVE_ANDROID_HISTORY_MANAGER_DESCRIPTION, kOsAndroid,
+      FEATURE_VALUE_TYPE(chrome::android::kNativeAndroidHistoryManager)},
 #endif  // OS_ANDROID
     {"enable-faster-location-reload", IDS_FLAGS_FASTER_LOCATION_RELOAD_NAME,
      IDS_FLAGS_FASTER_LOCATION_RELOAD_DESCRIPTION, kOsAll,

chrome/browser/android/chrome_feature_list.cc

@@ -47,6 +47,7 @@ const base::Feature* kFeaturesExposedToJava[] = {
     &kDownloadsUiFeature,
     &kImportantSitesInCBD,
     &kImprovedA2HS,
+    &kNativeAndroidHistoryManager,
     &kNoCreditCardAbort,
     &kNTPFakeOmniboxTextFeature,
     &kNTPOfflinePagesFeature,
@@ -100,6 +101,9 @@ const base::Feature kImportantSitesInCBD{"ImportantSitesInCBD",
 const base::Feature kImprovedA2HS{"ImprovedA2HS",
                                   base::FEATURE_DISABLED_BY_DEFAULT};
 
+const base::Feature kNativeAndroidHistoryManager{
+  "AndroidHistoryManager", base::FEATURE_DISABLED_BY_DEFAULT};
+
 const base::Feature kNoCreditCardAbort{"NoCreditCardAbort",
                                        base::FEATURE_DISABLED_BY_DEFAULT};
 

chrome/browser/android/chrome_feature_list.h

@@ -22,6 +22,7 @@ extern const base::Feature kContextualSearchSingleActions;
 extern const base::Feature kDownloadsUiFeature;
 extern const base::Feature kImportantSitesInCBD;
 extern const base::Feature kImprovedA2HS;
+extern const base::Feature kNativeAndroidHistoryManager;
 extern const base::Feature kNoCreditCardAbort;
 extern const base::Feature kNTPFakeOmniboxTextFeature;
 extern const base::Feature kNTPOfflinePagesFeature;

tools/metrics/histograms/histograms.xml

@@ -93663,6 +93663,7 @@ value.
   <int value="-13918890" label="disable-download-notification"/>
   <int value="-11260186" label="enable-offline-pages-as-saved-pages"/>
   <int value="-5052940" label="enable-simplified-fullscreen"/>
+  <int value="-2953333" label="AndroidHistoryManager:disabled"/>
   <int value="-2371418" label="disable-display-list-2d-canvas"/>
   <int value="0" label="BAD_FLAG_FORMAT">
     Command-line flag doesn't start with two dashes.
@@ -93820,6 +93821,7 @@ value.
   <int value="773919225" label="disable-office-editing-component-extension"/>
   <int value="779086132" label="enable-data-reduction-proxy-alt"/>
   <int value="782167080" label="enable-new-qp-input-view"/>
+  <int value="783270752" label="AndroidHistoryManager:enabled"/>
   <int value="803282885" label="PreferHtmlOverPlugins:disabled"/>
   <int value="805567148"
       label="enable-canvas-2d-dynamic-rendering-mode-switching"/>