[Media Router WebUI] Use I18nBehavior to retrieve strings.

chrome/browser/resources/media_router/elements/media_router_container/media_router_container.js

Index: chrome/browser/resources/media_router/elements/media_router_container/media_router_container.js
diff --git a/chrome/browser/resources/media_router/elements/media_router_container/media_router_container.js b/chrome/browser/resources/media_router/elements/media_router_container/media_router_container.js
index 1abb0d4a661cfaf1ef3c536d4e87b939fe73723b..624d10ac4002cbcfd597790c07fb12d750a385ad 100644
--- a/chrome/browser/resources/media_router/elements/media_router_container/media_router_container.js
+++ b/chrome/browser/resources/media_router/elements/media_router_container/media_router_container.js
@@ -121,37 +121,6 @@ Polymer({
     },
 
     /**
-     * The localized strings used by |this|.
-     * @private {!Object}
-     */
-    i18n_: {
-      readOnly: true,
-      type: Object,
-      value: function() {
-        var strings = {};
-        [
-          'deviceMissingText',
-          'firstRunFlowButtonText',
-          'firstRunFlowCloudPrefText',
-          'firstRunFlowText',
-          'firstRunFlowTitle',
-          'issueHeaderText',
-          'learnMoreText',
-          'searchButtonTitle',
-          'searchInputLabel',
-          'searchNoMatchesText',
-          'selectCastModeHeaderText',
-          'shareYourScreenSubheadingText',
-        ]
-        .forEach(function(s) {
-          strings[s] = loadTimeData.valueExists(s) ?
-              loadTimeData.getString(s) : '';
-        });
-        return strings;
-      },
-    },
-
-    /**
      * Whether the search input is currently focused. This is used to prevent
      * window focus/blur events from interfering with input-focus-dependent
      * operations.
@@ -388,6 +357,10 @@ Polymer({
     },
   },
 
+  behaviors: [
+    I18nBehavior,
+  ],
+
   listeners: {
     'focus': 'onFocus_',
     'header-height-changed': 'updateElementPositioning_',
@@ -641,9 +614,9 @@ Polymer({
   computeHeaderText_: function(view, headerText) {
     switch (view) {
       case media_router.MediaRouterView.CAST_MODE_LIST:
-        return this.i18n_['selectCastModeHeaderText'];
+        return this.i18n('selectCastModeHeaderText');
       case media_router.MediaRouterView.ISSUE:
-        return this.i18n_['issueHeaderText'];
+        return this.i18n('issueHeaderText');
       case media_router.MediaRouterView.ROUTE_DETAILS:
         return this.currentRoute_ ?
             this.sinkMap_[this.currentRoute_.sinkId].name : '';
@@ -1042,6 +1015,17 @@ Polymer({
   },
 
   /**
+   * Retrieves the first run flow cloud preferences text, if it exists. On
+   * non-officially branded builds, the string is not defined.
+   *
+   * @return {string} Cloud preferences text.
+   */
+  getFirstRunFlowCloudPrefText_: function() {
+    return loadTimeData.valueExists('firstRunFlowCloudPrefText') ?
+        this.i18n('firstRunFlowCloudPrefText') : '';
+  },
+
+  /**
    * Returns whether given string is undefined, null, empty, or whitespace only.
    * @param {?string} str String to be tested.
    * @return {boolean} |true| if the string is undefined, null, empty, or