MacViews: Clear mouse handler when showing context menus.

ui/views/controls/menu/menu_runner.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/views/controls/menu/menu_runner.h"
 
 #include <utility>
 
 #include "ui/views/controls/menu/menu_runner_handler.h"
 #include "ui/views/controls/menu/menu_runner_impl.h"
+#include "ui/views/widget/widget.h"
 
 namespace views {
 
 MenuRunner::MenuRunner(ui::MenuModel* menu_model, int32_t run_types)
     : run_types_(run_types),
       impl_(internal::MenuRunnerImplInterface::Create(menu_model, run_types)) {}
 
 MenuRunner::MenuRunner(MenuItemView* menu_view, int32_t run_types)
     : run_types_(run_types), impl_(new internal::MenuRunnerImpl(menu_view)) {}
 
@@ skipping 28 matching lines @@
         break;
       case ui::MENU_SOURCE_TOUCH:
       case ui::MENU_SOURCE_TOUCH_EDIT_MENU:
         anchor = MENU_ANCHOR_BOTTOMCENTER;
         break;
       default:
         break;
     }
   }
 
+  // If we are shown on mouse press, we will eat the subsequent mouse down and
+  // the parent widget will not be able to reset its state (it might have mouse
+  // capture from the mouse down). So we clear its state here.
+  if (parent && parent->GetRootView())

[sky, 2016/10/26 17:46:11]

Can you clarify why you need need to move this here rather than in
MenuController? Also, please provide test coverage. 

[themblsha, 2016/10/27 15:05:28]

As tapted suggested in his first comment, this seems to be a common place among
ToolbarButton, Combobox and the MenuController. It seems that we can remove all
these hacks by fixing the problem in a common place they all use.

Also added the test.

+    parent->GetRootView()->SetMouseHandler(nullptr);
+
   return impl_->RunMenuAt(parent, button, bounds, anchor, run_types_);
 }
 
 bool MenuRunner::IsRunning() const {
   return impl_->IsRunning();
 }
 
 void MenuRunner::Cancel() {
   impl_->Cancel();
 }
 
 base::TimeTicks MenuRunner::closing_event_time() const {
   return impl_->GetClosingEventTime();
 }
 
 void MenuRunner::SetRunnerHandler(
     std::unique_ptr<MenuRunnerHandler> runner_handler) {
   runner_handler_ = std::move(runner_handler);
 }
 
 }  // namespace views