Improved security of Quick View by rendering videos and audios inside webview.

ui/file_manager/file_manager/foreground/elements/files_safe_media.js

 // Copyright 2016 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.
 
 var FILES_APP_ORIGIN = 'chrome-extension://hhaomjibdihmijegdhdafkllkbggdgoj';
 
 /**
- * Polymer element to render an image securely inside webview.
- * When tapped, files-safe-img-tap-inside or
- * files-safe-img-tap-outside events are fired depending on the position
+ * Polymer element to render a media securely inside webview.
+ * When tapped, files-safe-media-tap-inside or
+ * files-safe-media-tap-outside events are fired depending on the position
  * of the tap.
  */
-var FilesSafeImg = Polymer({
-  is: 'files-safe-img',
+var FilesSafeMedia = Polymer({
+  is: 'files-safe-media',
 
   properties: {
     // URL accessible from webview.
     src: {
       type: String,
       observer: 'onSrcChange_',
       reflectToAttribute: true
+    },
+    type: {
+      type: String,
+      readonly: true,
     }
   },
 
   listeners: {'src-changed': 'onSrcChange_'},
 
+  /**
+   * @return {string}
+   */
+  sourceFile_: function() {
+    switch (this.type) {
+      case 'image':
+         return 'foreground/elements/files_safe_img_webview_content.html';
+      case 'audio':
+         return 'foreground/elements/files_safe_audio_webview_content.html';
+      case 'video':
+         return 'foreground/elements/files_safe_video_webview_content.html';
+      default:
+        console.error('Unsupported type: ' + this.type);
+        return '';
+    }
+  },
+
   onSrcChange_: function() {
     if (!this.src && this.webview_) {
       // Remove webview to clean up unnecessary processes.
       Polymer.dom(this.$.content).removeChild(this.webview_);
       this.webview_ = null;
     } else if (this.src && !this.webview_) {
       // Create webview node only if src exists to save resouces.
       var webview = document.createElement('webview');
       this.webview_ = webview;
       webview.partition = 'trusted';
       webview.allowtransparency = 'true';
       Polymer.dom(this.$.content).appendChild(webview);
       webview.addEventListener(
           'contentload', this.onSrcChange_.bind(this));
-      webview.src = 'foreground/elements/files_safe_img_webview_content.html';
+      webview.src = this.sourceFile_();
     } else if (this.src && this.webview_.contentWindow) {
       this.webview_.contentWindow.postMessage(this.src, FILES_APP_ORIGIN);
     }
   },
 
   created: function() {
     /**
      * @type {HTMLElement}
      */
     this.webview_ = null;
   },
 
   ready: function() {
     window.addEventListener('message', function(event) {
       if (event.origin !== FILES_APP_ORIGIN) {
-        console.error('Unknown origin.');
+        console.log('Unknown origin.');
         return;
       }
       if (event.data === 'tap-inside') {
-        this.fire('files-safe-img-tap-inside');
+        this.fire('files-safe-media-tap-inside');
       } else if (event.data === 'tap-outside') {
-        this.fire('files-safe-img-tap-outside');
+        this.fire('files-safe-media-tap-outside');
       }
     }.bind(this));
   }
 });