Show ARC IME names in chrome://settings/inputMethods

ARC IMEs added via Play Store are not associated with any language
by design. Instead, each IME supports only one fake language
|kArcImeLanguage| defined in ui/base/ime/chromeos/.

This CL allows chrome://settings/inputMethods to show such IMEs
at the bottom of the list by doing the following:

 - Return |kArcImeLanguage| and its display name from the
   GetLanguageList() private API.
 - Do not show the fake language in add_languages_dialog.js since
   it's for internal use only.
 - Modify manage_input_methods_page.js to show ARC IMEs associated
   with |kArcImeLanguage|.
 - Handle ARC IMEs in the AddInputMethod() private API.

Bug: b:74499980
Bug: 845079
Cq-Include-Trybots: luci.chromium.try:closure_compilation
Change-Id: I28a1b01705387dc9cd87dd0b873dc3ca23087cbf
Reviewed-on: https://chromium-review.googlesource.com/1114680Reviewed-by: Steven Bennetts <stevenjb@chromium.org>
Reviewed-by: Yuichiro Hanada <yhanada@chromium.org>
Commit-Queue: Yusuke Sato <yusukes@chromium.org>
Cr-Commit-Position: refs/heads/master@{#571343}

chrome/app/settings_strings.grdp

@@ -2309,6 +2309,9 @@
     <message name="IDS_SETTINGS_LANGUAGES_SHOW_IME_MENU" desc="The label for he toggle button controlling showing the IME menu in the shelf.">
       Show input options in the shelf
     </message>
+    <message name="IDS_SETTINGS_LANGUAGES_KEYBOARD_APPS" desc="Title for the list of keyboard apps installed via Play Store by the user.">
+      Keyboard apps
+    </message>
   </if>
   <message name="IDS_SETTINGS_LANGUAGES_MANAGE_LANGUAGES_TITLE" desc="Name of the settings dialog which allows enabling additional languages.">
     Add languages

chrome/browser/extensions/api/language_settings_private/language_settings_private_api.cc

@@ -43,6 +43,7 @@
 #include "ui/base/l10n/l10n_util_collator.h"
 
 #if defined(OS_CHROMEOS)
+#include "chrome/grit/generated_resources.h"
 #include "ui/base/ime/chromeos/component_extension_ime_manager.h"
 #include "ui/base/ime/chromeos/extension_ime_util.h"
 #include "ui/base/ime/chromeos/input_method_manager.h"
@@ -144,6 +145,10 @@ std::vector<std::string> GetSortedExtensionIMEs(
       base::SplitString(preferred_languages, ",", base::TRIM_WHITESPACE,
                         base::SPLIT_WANT_NONEMPTY);
 
+  // Add the fake language for ARC IMEs at the very last of the list. Unlike
+  // Chrome OS IMEs, these ARC ones are not associated with any (real) language.
+  enabled_languages.push_back(chromeos::extension_ime_util::kArcImeLanguage);
+
   InputMethodDescriptors descriptors;
   ime_state->GetInputMethodExtensions(&descriptors);
 
@@ -243,6 +248,20 @@ LanguageSettingsPrivateGetLanguageListFunction::Run() {
 
     language_list->Append(language.ToValue());
   }
+
+#if defined(OS_CHROMEOS)
+  // Send the display name of the fake language for ARC IMEs to the JS side.
+  // |native_display_name| does't have to be set because the language selection
+  // drop-down menu doesn't list the fake language.
+  {
+    language_settings_private::Language language;
+    language.code = chromeos::extension_ime_util::kArcImeLanguage;
+    language.display_name =
+        l10n_util::GetStringUTF8(IDS_SETTINGS_LANGUAGES_KEYBOARD_APPS);
+    language_list->Append(language.ToValue());
+  }
+#endif  // defined(OS_CHROMEOS)
+
   return RespondNow(OneArgument(std::move(language_list)));
 }
 

chrome/browser/extensions/api/language_settings_private/language_settings_private_api_unittest.cc

@@ -180,15 +180,17 @@ class TestInputMethodManager : public input_method::MockInputMethodManager {
       // Set up three IMEs
       std::vector<std::string> layouts({"us"});
       std::vector<std::string> languages({"en-US"});
+      std::vector<std::string> arc_languages(
+          {chromeos::extension_ime_util::kArcImeLanguage});
       InputMethodDescriptor extension_ime(
           GetExtensionImeId(), "", "", layouts, languages,
           false /* is_login_keyboard */, GURL(), GURL());
       InputMethodDescriptor component_extension_ime(
           GetComponentExtensionImeId(), "", "", layouts, languages,
           false /* is_login_keyboard */, GURL(), GURL());
-      InputMethodDescriptor arc_ime(GetArcImeId(), "", "", layouts, languages,
-                                    false /* is_login_keyboard */, GURL(),
-                                    GURL());
+      InputMethodDescriptor arc_ime(
+          GetArcImeId(), "", "", layouts, arc_languages,
+          false /* is_login_keyboard */, GURL(), GURL());
       input_methods_ = {extension_ime, component_extension_ime, arc_ime};
     }
 

chrome/browser/resources/settings/languages_page/add_languages_dialog.js

@@ -83,6 +83,9 @@ Polymer({
       if (!isAvailableLanguage)
         return false;
 
+      if (this.languageHelper.isLanguageCodeForArcIme(language.code))
+        return false;  // internal use only
+
       if (filterValue === null)
         return true;
 

chrome/browser/resources/settings/languages_page/languages.js

@@ -35,6 +35,10 @@ const kTranslateLanguageSynonyms = {
   'jv': 'jw',
 };
 
+// The fake language name used for ARC IMEs. The value must be in sync with the
+// one in ui/base/ime/chromeos/extension_ime_util.h.
+const kArcImeLanguage = '_arc_ime_language_';
+
 const preferredLanguagesPrefName = cr.isChromeOS ?
     'settings.language.preferred_languages' :
     'intl.accept_languages';
@@ -661,6 +665,21 @@ Polymer({
   },
   // </if>
 
+  /**
+   * @return {string} The language code for ARC IMEs.
+   */
+  getArcImeLanguageCode: function() {
+    return kArcImeLanguage;
+  },
+
+  /**
+   * @param {string} languageCode
+   * @return {boolean} True if the language is for ARC IMEs.
+   */
+  isLanguageCodeForArcIme: function(languageCode) {
+    return languageCode == kArcImeLanguage;
+  },
+
   /**
    * @param {string} languageCode
    * @return {boolean} True if the language is enabled.

chrome/browser/resources/settings/languages_page/languages_types.js

@@ -96,6 +96,17 @@ class LanguageHelper {
 
   // </if>
 
+  /**
+   * @return {string} The language code for ARC IMEs.
+   */
+  getArcImeLanguageCode() {}
+
+  /**
+   * @param {string} languageCode
+   * @return {boolean}
+   */
+  isLanguageCodeForArcIme(languageCode) {}
+
   /**
    * @param {string} languageCode
    * @return {boolean}

chrome/browser/resources/settings/languages_page/manage_input_methods_page.js

@@ -153,6 +153,17 @@ Polymer({
         usedLanguages.add(languageFamilyCodes[k]);
     }
 
+    // Add ARC IMEs to the bottom if any.
+    const arcInputMethods = this.getInputMethodsForLanguages(
+        [this.languageHelper.getArcImeLanguageCode()]);
+    if (arcInputMethods.length) {
+      languageList.push({
+        language: this.languageHelper.getLanguage(
+            this.languageHelper.getArcImeLanguageCode()),
+        inputMethods: arcInputMethods,
+      });
+    }
+
     this.languageList_ = languageList;
     this.notifyInputMethodsChanged_();
   },

chrome/test/data/webui/settings/fake_language_settings_private.js

@@ -106,6 +106,13 @@ cr.define('settings', function() {
           displayName: 'Greek',
           nativeDisplayName: 'Ελληνικά',
           supportsUI: true,
+        },
+        {
+          // A fake language for ARC IMEs which is for internal use only. The
+          // value of the |code| must be the same as |kArcImeLanguage| in
+          // ui/base/ime/chromeos/extension_ime_util.cc.
+          code: '_arc_ime_language_',
+          displayName: 'Keyboard apps',
         }
       ];
 

chrome/test/data/webui/settings/languages_page_tests.js

@@ -212,6 +212,11 @@ cr.define('languages_page_tests', function() {
         searchInput.setValue('egaugnal');
         Polymer.dom.flush();
         assertEquals(0, getItems().length);
+
+        // Issue query that should never match any language.
+        searchInput.setValue('_arc_ime_language_');
+        Polymer.dom.flush();
+        assertEquals(0, getItems().length);
       });
 
       test('Escape key behavior', function() {