Add experimental Support for DOM3 KeyboardEvent key value

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 261 matching lines @@
 
         var type;
         switch (event.type) {
         case "keydown": type = "keyDown"; break;
         case "keyup": type = "keyUp"; break;
         case "keypress": type = "char"; break;
         default: return;
         }
 
         var text = event.type === "keypress" ? String.fromCharCode(event.charCode) : undefined;
-        this._target.inputAgent().dispatchKeyEvent(type, this._modifiersForEvent(event), event.timeStamp / 1000, text, text ? text.toLowerCase() : undefined,
-                                    event.keyIdentifier, event.code, event.keyCode /* windowsVirtualKeyCode */, event.keyCode /* nativeVirtualKeyCode */, false, false, false);
+        this._target.inputAgent().invoke_dispatchKeyEvent({
+            type: type,
+            modifiers: this._modifiersForEvent(event),
+            timestamp: event.timeStamp / 1000,
+            text: text,
+            unmodifiedText: text ? text.toLowerCase() : undefined,
+            keyIdentifier: event.keyIdentifier,
+            code: event.code,
+            key: event.key,
+            windowsVirtualKeyCode: event.keyCode /* windowsVirtualKeyCode */,
+            nativeVirtualKeyCode: event.keyCode /* nativeVirtualKeyCode */,
+            autoRepeat: false,
+            isKeypad: false,
+            isSystemKey: false});
         event.consume();
         this._canvasElement.focus();
     },
 
     /**
      * @param {!Event} event
      */
     _handleContextMenuEvent: function(event)
     {
         event.consume(true);
@@ skipping 572 matching lines @@
           return;
         this._maxDisplayedProgress = progress;
         this._displayProgress(progress);
     },
 
     _displayProgress: function(progress)
     {
         this._element.style.width = (100 * progress) + "%";
     }
 };