[Media Router WebUI] Use I18nBehavior to retrieve strings.

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

 // Copyright 2015 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.
 
 // This Polymer element is used to show information about issues related
 // to casting.
 Polymer({
   is: 'issue-banner',
 
   properties: {
@@ skipping 34 matching lines @@
     /**
      * The text shown in the secondary action button.
      * @private {string}
      */
     secondaryActionButtonText_: {
       type: String,
       value: '',
     },
   },
 
+  behaviors: [
+    I18nBehavior,
+  ],
+
   /**
    * @param {?media_router.Issue} issue
    * @return {boolean} Whether or not to hide the blocking issue UI.
    * @private
    */
   computeIsBlockingIssueHidden_: function(issue) {
     return !issue || !issue.isBlocking;
   },
 
   /**
@@ skipping 55 matching lines @@
   /**
    * Called when |issue| is updated. This updates the default and secondary
    * action button text.
    *
    * @private
    */
   updateActionButtonText_: function() {
     var defaultText = '';
     var secondaryText = '';
     if (this.issue) {
-      defaultText = loadTimeData.getString(
-          this.actionTypeToButtonTextResource_[
-          this.issue.defaultActionType]);
+      defaultText =
+          this.i18n(this.actionTypeToButtonTextResource_[
+              this.issue.defaultActionType]);
 
       if (this.issue.secondaryActionType) {
-        secondaryText = loadTimeData.getString(
-            this.actionTypeToButtonTextResource_[
-            this.issue.secondaryActionType]);
+        secondaryText =
+            this.i18n(this.actionTypeToButtonTextResource_[
+                this.issue.secondaryActionType]);
       }
     }
 
     this.defaultActionButtonText_ = defaultText;
     this.secondaryActionButtonText_ = secondaryText;
   },
 });