Don't pass touches to gesture recognizer for async acks.

ui/aura/test/aura_test_utils.cc

 // Copyright 2014 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/test/aura_test_utils.h"
 
+#include "ui/aura/window_event_dispatcher.h"
 #include "ui/aura/window_tree_host.h"
 
 namespace aura {
 namespace test {
 
 class WindowTreeHostTestApi {
  public:
   explicit WindowTreeHostTestApi(WindowTreeHost* host) : host_(host) {}
 
   const gfx::Point& last_cursor_request_position_in_host() {
     return host_->last_cursor_request_position_in_host_;
   }
 
+  void set_dispatcher(scoped_ptr<WindowEventDispatcher> dispatcher) {
+    host_->dispatcher_ = dispatcher.Pass();
+  }
+
  private:
   WindowTreeHost* host_;
 
   DISALLOW_COPY_AND_ASSIGN(WindowTreeHostTestApi);
 };
 
 const gfx::Point& QueryLatestMousePositionRequestInHost(WindowTreeHost* host) {
   WindowTreeHostTestApi host_test_api(host);
   return host_test_api.last_cursor_request_position_in_host();
 }
 
+void SetHostDispatcher(WindowTreeHost* host,
+                       scoped_ptr<WindowEventDispatcher> dispatcher) {
+  WindowTreeHostTestApi host_test_api(host);
+  host_test_api.set_dispatcher(dispatcher.Pass());
+}
+
 }  // namespace test
 }  // namespace aura