Dispatch key events to the currently focused window.

mojo/services/public/cpp/view_manager/lib/view.cc

Index: mojo/services/public/cpp/view_manager/lib/view.cc
diff --git a/mojo/services/public/cpp/view_manager/lib/view.cc b/mojo/services/public/cpp/view_manager/lib/view.cc
index bedac6b67b6bea406fb55d0288a3bec5f9295e67..4dc45227fcb36139a692e624b5728fd8cec934e3 100644
--- a/mojo/services/public/cpp/view_manager/lib/view.cc
+++ b/mojo/services/public/cpp/view_manager/lib/view.cc
@@ -270,6 +270,13 @@ void View::RemoveObserver(ViewObserver* observer) {
   observers_.RemoveObserver(observer);
 }
 
+const View* View::GetRoot() const {
+  const View* root = this;
+  for (const View* parent = this; parent; parent = parent->parent())
+    root = parent;
+  return root;
+}
+
 void View::AddChild(View* child) {
   // TODO(beng): not necessarily valid to all connections, but possibly to the
   //             embeddee in an embedder-embeddee relationship.