Remove some confusing code from ToplevelWindowEventHandler::HandleMousePressed()

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 369 matching lines @@
   drag_reverted_ = (status == DRAG_REVERT);
 
   in_gesture_drag_ = false;
   if (in_move_loop_)
     quit_closure_.Run();
 }
 
 void ToplevelWindowEventHandler::HandleMousePressed(
     aura::Window* target,
     ui::MouseEvent* event) {
-  // Move/size operations are initiated post-target handling to give the target
-  // an opportunity to cancel this default behavior by returning ER_HANDLED.
-  if (ui::EventCanceledDefaultHandling(*event))
+  if (event->phase() != ui::EP_PRETARGET)
     return;
 
   // We also update the current window component here because for the
   // mouse-drag-release-press case, where the mouse is released and
   // pressed without mouse move event.
   int component =
       target->delegate()->GetNonClientComponent(event->location());
   if ((event->flags() &
         (ui::EF_IS_DOUBLE_CLICK | ui::EF_IS_TRIPLE_CLICK)) == 0 &&
       WindowResizer::GetBoundsChangeForWindowComponent(component)) {
@@ skipping 125 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, 0);
 }
 
 }  // namespace ash