Roll 50: Updated for push to origin/master.

tools/dom/src/dartium_KeyEvent.dart

 /**
  * A custom KeyboardEvent that attempts to eliminate cross-browser
  * inconsistencies, and also provide both keyCode and charCode information
  * for all key events (when such information can be determined).
  *
  * KeyEvent tries to provide a higher level, more polished keyboard event
  * information on top of the "raw" [KeyboardEvent].
  *
  * The mechanics of using KeyEvents is a little different from the underlying
  * [KeyboardEvent]. To use KeyEvents, you need to create a stream and then add
@@ skipping 49 matching lines @@
 
   /** Accessor to the underlying charCode value is the parent event. */
   int get _realCharCode => _parent.charCode;
 
   /** Accessor to the underlying altKey value is the parent event. */
   bool get _realAltKey => _parent.altKey;
 
   /** Shadows on top of the parent's currentTarget. */
   EventTarget _currentTarget;
 
+  final InputDeviceCapabilities sourceCapabilities;
+
   /** Construct a KeyEvent with [parent] as the event we're emulating. */
   KeyEvent.wrap(KeyboardEvent parent) : super(parent) {
     _parent = parent;
     _shadowAltKey = _realAltKey;
     _shadowCharCode = _realCharCode;
     _shadowKeyCode = _realKeyCode;
     _currentTarget =
         _parent.currentTarget == null ? window : _parent.currentTarget;
   }
 
@@ skipping 84 matching lines @@
   }
 
   @Experimental() // untriaged
   bool getModifierState(String keyArgument) => throw new UnimplementedError();
   @Experimental() // untriaged
   int get location => throw new UnimplementedError();
   @Experimental() // untriaged
   bool get repeat => throw new UnimplementedError();
   dynamic get _get_view => throw new UnimplementedError();
 }