[M-37]: Fix dragging tab via mouse when touch is down on ChromeOS

ash/wm/toplevel_window_event_handler.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 "ash/wm/toplevel_window_event_handler.h"
 
 #include "ash/shell.h"
 #include "ash/wm/resize_shadow_controller.h"
 #include "ash/wm/window_resizer.h"
 #include "ash/wm/window_state.h"
@@ skipping 465 matching lines @@
         (ui::EF_IS_DOUBLE_CLICK | ui::EF_IS_TRIPLE_CLICK)) == 0 &&
       WindowResizer::GetBoundsChangeForWindowComponent(component)) {
     gfx::Point location_in_parent(
         ConvertPointToParent(target, event->location()));
     AttemptToStartDrag(target, location_in_parent, component,
                        aura::client::WINDOW_MOVE_SOURCE_MOUSE);
     // Set as handled so that other event handlers do no act upon the event
     // but still receive it so that they receive both parts of each pressed/
     // released pair.
     event->SetHandled();
   } else {

[pkotwicz, 2014/06/29 16:00:40]

We should also avoid calling CompleteDrag() here if the drag has already been
completed. I will fix this up as part of another CL.

[oshima, 2014/07/01 17:52:01]

Why another CL? Don't we want to fix them all and merge it?

[pkotwicz, 2014/07/04 14:28:41]

I wanted to keep the CL to be merged as small as possible

     CompleteDrag(DRAG_COMPLETE);
   }
 }
 
 void ToplevelWindowEventHandler::HandleMouseReleased(
     aura::Window* target,
     ui::MouseEvent* event) {
   if (event->phase() != ui::EP_PRETARGET)
     return;
 
-  CompleteDrag(event->type() == ui::ET_MOUSE_RELEASED ?
-                   DRAG_COMPLETE : DRAG_REVERT);
+  if (window_resizer_) {

[pkotwicz, 2014/06/28 18:37:36]

We should also avoid calling CompleteDrag() here if the drag has already been
completed. I will fix this up as part of another CL.

[varkha, 2014/07/04 23:09:01]

Should this method just return early when !window_resizer_? This would simplify
the logic here and below.

+    CompleteDrag(event->type() == ui::ET_MOUSE_RELEASED ?
+                     DRAG_COMPLETE : DRAG_REVERT);
+  }
+
   // Completing the drag may result in hiding the window. If this happens
   // mark the event as handled so no other handlers/observers act upon the
   // event. They should see the event on a hidden window, to determine targets
   // of destructive actions such as hiding. They should not act upon them.
   if (window_resizer_ &&
       event->type() == ui::ET_MOUSE_CAPTURE_CHANGED &&
       !target->IsVisible()) {

[pkotwicz, 2014/06/28 18:37:36]

This code never gets run. (That's as a result of a bad suggestion on a CL on my
part.) I am going to fix it up in a different CL.

     event->SetHandled();
   }
 }
 
 void ToplevelWindowEventHandler::HandleDrag(
     aura::Window* target,
     ui::LocatedEvent* event) {
   // This function only be triggered to move window
   // by mouse drag or touch move event.
   DCHECK(event->type() == ui::ET_MOUSE_DRAGGED ||
@@ skipping 93 matching lines @@
 
 void ToplevelWindowEventHandler::ResizerWindowDestroyed() {
   // We explicitly don't invoke RevertDrag() since that may do things to window.
   // Instead we destroy the resizer.
   window_resizer_.reset();
 
   CompleteDrag(DRAG_REVERT);
 }
 
 }  // namespace ash