[DevTools] Introduce EmulationModel which will encapsulate emulation

third_party/WebKit/Source/devtools/front_end/screencast/ScreencastView.js

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 112 matching lines @@
       this._isCasting = false;
       return;
     }
     dimensions.width *= window.devicePixelRatio;
     dimensions.height *= window.devicePixelRatio;
     // Note: startScreencast width and height are expected to be integers so must be floored.
     this._screenCaptureModel.startScreencast(
         'jpeg', 80, Math.floor(Math.min(maxImageDimension, dimensions.width)),
         Math.floor(Math.min(maxImageDimension, dimensions.height)), undefined, this._screencastFrame.bind(this),
         this._screencastVisibilityChanged.bind(this));
-    Emulation.MultitargetTouchModel.instance().setCustomTouchEnabled(true);
+    for (var emulationModel of SDK.targetManager.models(SDK.EmulationModel))
+      emulationModel.overrideEmulateTouch(true);
     if (this._overlayModel)
       this._overlayModel.setHighlighter(this);
   }
 
   _stopCasting() {
     if (!this._isCasting)
       return;
     this._isCasting = false;
     this._screenCaptureModel.stopScreencast();
-    Emulation.MultitargetTouchModel.instance().setCustomTouchEnabled(false);
+    for (var emulationModel of SDK.targetManager.models(SDK.EmulationModel))
+      emulationModel.overrideEmulateTouch(false);
     if (this._overlayModel)
       this._overlayModel.setHighlighter(null);
   }
 
   /**
    * @param {string} base64Data
    * @param {!Protocol.Page.ScreencastFrameMetadata} metadata
    */
   _screencastFrame(base64Data, metadata) {
     this._imageElement.onload = () => {
@@ skipping 613 matching lines @@
     if (this._maxDisplayedProgress >= progress)
       return;
     this._maxDisplayedProgress = progress;
     this._displayProgress(progress);
   }
 
   _displayProgress(progress) {
     this._element.style.width = (100 * progress) + '%';
   }
 };