Roll 50: Updated for push to origin/master.

tools/dom/src/dartium_KeyEvent.dart

Index: tools/dom/src/dartium_KeyEvent.dart
diff --git a/tools/dom/src/dartium_KeyEvent.dart b/tools/dom/src/dartium_KeyEvent.dart
index 00a1b2a726b4274044a227d5f3dcf5d547618d52..6c8ad56381c28c08a182ba7ac5d78714e034baac 100644
--- a/tools/dom/src/dartium_KeyEvent.dart
+++ b/tools/dom/src/dartium_KeyEvent.dart
@@ -67,6 +67,8 @@ class KeyEvent extends _WrappedEvent implements KeyboardEvent {
   /** 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;