Remove stops_event_propagation from Window, since it's broken.

ui/aura/client/event_client.cc

+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "ui/aura/client/event_client.h"
+
+#include "ui/aura/root_window.h"
+#include "ui/aura/window_property.h"
+
+DECLARE_WINDOW_PROPERTY_TYPE(aura::client::EventClient*)
+
+namespace aura {
+namespace client {
+
+DEFINE_WINDOW_PROPERTY_KEY(EventClient*, kRootWindowEventClientKey, NULL);
+
+void SetEventClient(RootWindow* root_window, EventClient* client) {
+  root_window->SetProperty(kRootWindowEventClientKey, client);
+}
+
+EventClient* GetEventClient(const RootWindow* root_window) {
+  return root_window ?
+      root_window->GetProperty(kRootWindowEventClientKey) : NULL;
+}
+
+}  // namespace client
+}  // namespace aura