[DevTools] Make resource tree model optional

third_party/WebKit/Source/devtools/front_end/emulation/DeviceModeView.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.
 
 /**
  * @constructor
  * @extends {WebInspector.VBox}
  */
 WebInspector.DeviceModeView = function()
 {
@@ skipping 454 matching lines @@
              */
             function paintScreenshot()
             {
                 var pageImage = new Image();
                 pageImage.src = "data:image/png;base64," + content;
                 ctx.drawImage(pageImage,
                               visiblePageRect.left,
                               visiblePageRect.top,
                               Math.min(pageImage.naturalWidth, screenRect.width),
                               Math.min(pageImage.naturalHeight, screenRect.height));
-                var mainFrame = mainTarget.resourceTreeModel.mainFrame;
+                var resourceTreeModel = mainTarget && WebInspector.ResourceTreeModel.fromTarget(mainTarget);
+                var mainFrame = resourceTreeModel && resourceTreeModel.mainFrame;
                 var fileName = mainFrame ? mainFrame.url.trimURL().removeURLFragment() : "";

[dgozman, 2016/08/19 20:23:37]

All this code looks like WI.targetManager.inspectedPageURL().removeURLFragment()

[eostroukhov, 2016/08/20 01:22:30]

Done.

                 if (this._model.type() === WebInspector.DeviceModeModel.Type.Device)
                     fileName += WebInspector.UIString("(%s)", this._model.device().title);
                 // Trigger download.
                 var link = createElement("a");
                 link.download = fileName + ".png";
                 link.href = canvas.toDataURL("image/png");
                 link.click();
             }
         }
     },
@@ skipping 99 matching lines @@
     /**
      * @param {number} size
      */
     _onMarkerClick: function(size)
     {
         this._applyCallback.call(null, size);
     },
 
     __proto__: WebInspector.VBox.prototype
 }