Turn RootWindowController Menus Async

ui/views/widget/widget.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/widget/widget.h"
 
 #include "base/logging.h"
 #include "base/macros.h"
 #include "base/message_loop/message_loop.h"
 #include "base/strings/utf_string_conversions.h"
@@ skipping 1153 matching lines @@
 void Widget::OnMouseEvent(ui::MouseEvent* event) {
   View* root_view = GetRootView();
   switch (event->type()) {
     case ui::ET_MOUSE_PRESSED: {
       last_mouse_event_was_move_ = false;
 
       // We may get deleted by the time we return from OnMousePressed. So we
       // use an observer to make sure we are still alive.
       WidgetDeletionObserver widget_deletion_observer(this);
 
+      gfx::NativeView current_capture =
+          internal::NativeWidgetPrivate::GetCapture(
+              native_widget_->GetNativeView());
       // Make sure we're still visible before we attempt capture as the mouse
       // press processing may have made the window hide (as happens with menus).
 
-      // It is possible for a View to show a context menu on mouse-press. Since
-      // the menu does a capture and starts a nested message-loop, the release
-      // would go to the menu. The next click (i.e. both mouse-press and release
-      // events) also go to the menu. The menu (and the nested message-loop)
-      // gets closed after this second release event. The code then resumes from
-      // here. So make sure that the mouse-button is still down before doing a
-      // capture.
+      // It is possible for a View to show a context menu on mouse-press, which

[sky, 2016/05/06 20:03:32]

Can you make this comment more general and not entirely menu specific. Basically
we're assuming that if the capture changed during the processing of the mouse
down that a nested message loop was started and we shouldn't set internal state.

[jonross, 2016/05/09 16:50:25]

Done.

+      // takes capture.
+      //
+      // Menus which use a nested message-loop, receive the release. The next
+      // click (i.e. both mouse-press and release events) also go to the menu.
+      // The menu (and the nested message-loop) gets closed after this second
+      // release event. The code then resumes from here. So make sure that the
+      // mouse-button is still down before doing a capture.
+      //
+      // Menus which do not use a nested message-loop will return here, holding
+      // capture. This will lead to capture having changed, in which case we do
+      // not give capture back to the |native_widget_|.
       if (root_view && root_view->OnMousePressed(*event) &&
           widget_deletion_observer.IsWidgetAlive() && IsVisible() &&
-          internal::NativeWidgetPrivate::IsMouseButtonDown()) {
+          internal::NativeWidgetPrivate::IsMouseButtonDown() &&
+          current_capture == internal::NativeWidgetPrivate::GetCapture(
+                                 native_widget_->GetNativeView())) {
         is_mouse_button_pressed_ = true;
         if (!native_widget_->HasCapture())
           native_widget_->SetCapture();
         event->SetHandled();
       }
       return;
     }
 
     case ui::ET_MOUSE_RELEASED:
       last_mouse_event_was_move_ = false;
@@ skipping 286 matching lines @@
 
 ////////////////////////////////////////////////////////////////////////////////
 // internal::NativeWidgetPrivate, NativeWidget implementation:
 
 internal::NativeWidgetPrivate* NativeWidgetPrivate::AsNativeWidgetPrivate() {
   return this;
 }
 
 }  // namespace internal
 }  // namespace views