Use a single ToplevelWindowEventHandler for the ash::Shell

ash/wm/workspace/workspace_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/workspace/workspace_event_handler.h"
 
 #include "ash/screen_ash.h"
 #include "ash/shell.h"
 #include "ash/shell_delegate.h"
 #include "ash/touch/touch_uma.h"
@@ skipping 36 matching lines @@
     }
   } else if (window_state->CanMaximize()) {
     window_state->Maximize();
   }
 }
 
 }  // namespace
 
 namespace internal {
 
-WorkspaceEventHandler::WorkspaceEventHandler(aura::Window* owner)
-    : ToplevelWindowEventHandler(owner),
-      destroyed_(NULL) {
+WorkspaceEventHandler::WorkspaceEventHandler() {
 }
 
 WorkspaceEventHandler::~WorkspaceEventHandler() {
-  if (destroyed_)
-    *destroyed_ = true;
 }
 
 void WorkspaceEventHandler::OnMouseEvent(ui::MouseEvent* event) {
   aura::Window* target = static_cast<aura::Window*>(event->target());
   switch (event->type()) {
     case ui::ET_MOUSE_MOVED: {
       int component =
           target->delegate()->GetNonClientComponent(event->location());
       multi_window_resize_controller_.Show(target, component,
                                            event->location());
       break;
     }
     case ui::ET_MOUSE_ENTERED:
       break;
     case ui::ET_MOUSE_CAPTURE_CHANGED:
     case ui::ET_MOUSE_EXITED:
       break;
     case ui::ET_MOUSE_PRESSED: {
       // Maximize behavior is implemented as post-target handling so the target
       // can cancel it.
-      if (ui::EventCanceledDefaultHandling(*event)) {
-        ToplevelWindowEventHandler::OnMouseEvent(event);
+      if (ui::EventCanceledDefaultHandling(*event))
         return;
-      }
       wm::WindowState* target_state = wm::GetWindowState(target);
       if (event->flags() & ui::EF_IS_DOUBLE_CLICK &&
           event->IsOnlyLeftMouseButton() &&
           target->delegate()->GetNonClientComponent(event->location()) ==
           HTCAPTION) {
-        bool destroyed = false;
-        destroyed_ = &destroyed;
         ash::Shell::GetInstance()->delegate()->RecordUserMetricsAction(
             ash::UMA_TOGGLE_MAXIMIZE_CAPTION_CLICK);
         ToggleMaximizedState(target_state);
-        if (destroyed)
-          return;
-        destroyed_ = NULL;
+        event->StopPropagation();
       }
       multi_window_resize_controller_.Hide();
       HandleVerticalResizeDoubleClick(target_state, event);
       break;
     }
     default:
       break;
   }
-  ToplevelWindowEventHandler::OnMouseEvent(event);
 }
 
 void WorkspaceEventHandler::OnGestureEvent(ui::GestureEvent* event) {
   aura::Window* target = static_cast<aura::Window*>(event->target());
   if (event->type() == ui::ET_GESTURE_TAP &&
       target->delegate()->GetNonClientComponent(event->location()) ==
       HTCAPTION) {
     if (event->details().tap_count() == 2) {
       ash::Shell::GetInstance()->delegate()->RecordUserMetricsAction(
           ash::UMA_TOGGLE_MAXIMIZE_CAPTION_GESTURE);
       // Note: TouchUMA::GESTURE_FRAMEVIEW_TAP is counted twice each time
       // TouchUMA::GESTURE_MAXIMIZE_DOUBLETAP is counted once.
       TouchUMA::GetInstance()->RecordGestureAction(
           TouchUMA::GESTURE_MAXIMIZE_DOUBLETAP);
-      // |this| may be destroyed from here.
       ToggleMaximizedState(wm::GetWindowState(target));
       event->StopPropagation();
       return;
     } else {
       // Note: TouchUMA::GESTURE_FRAMEVIEW_TAP is counted twice for each tap.
       TouchUMA::GetInstance()->RecordGestureAction(
           TouchUMA::GESTURE_FRAMEVIEW_TAP);
     }
   }
-  ToplevelWindowEventHandler::OnGestureEvent(event);
 }
 
 void WorkspaceEventHandler::HandleVerticalResizeDoubleClick(
     wm::WindowState* target_state,
     ui::MouseEvent* event) {
   aura::Window* target = target_state->window();
   gfx::Rect max_size(target->delegate()->GetMaximumSize());
   if (event->flags() & ui::EF_IS_DOUBLE_CLICK && !target_state->IsMaximized()) {
     int component =
         target->delegate()->GetNonClientComponent(event->location());
     gfx::Rect work_area = Shell::GetScreen()->GetDisplayNearestWindow(
         target).work_area();
     if (component == HTBOTTOM || component == HTTOP) {
       // Don't maximize vertically if the window has a max height defined.
       if (max_size.height() != 0)
         return;
       if (target_state->HasRestoreBounds() &&
           (target->bounds().height() == work_area.height() &&
            target->bounds().y() == work_area.y())) {
         SingleAxisUnmaximize(target_state,
                              target_state->GetRestoreBoundsInScreen());
+        event->StopPropagation();
       } else {
         gfx::Point origin = target->bounds().origin();
         wm::ConvertPointToScreen(target->parent(), &origin);
         SingleAxisMaximize(target_state,
                            gfx::Rect(origin.x(),
                                      work_area.y(),
                                      target->bounds().width(),
                                      work_area.height()));
+        event->StopPropagation();
       }
     } else if (component == HTLEFT || component == HTRIGHT) {
       // Don't maximize horizontally if the window has a max width defined.
       if (max_size.width() != 0)
         return;
       if (target_state->HasRestoreBounds() &&
           (target->bounds().width() == work_area.width() &&
            target->bounds().x() == work_area.x())) {
         SingleAxisUnmaximize(target_state,
                              target_state->GetRestoreBoundsInScreen());
+        event->StopPropagation();
       } else {
         gfx::Point origin = target->bounds().origin();
         wm::ConvertPointToScreen(target->parent(), &origin);
         SingleAxisMaximize(target_state,
                            gfx::Rect(work_area.x(),
                                      origin.y(),
                                      work_area.width(),
                                      target->bounds().height()));
+        event->StopPropagation();
       }
     }
   }
 }
 
 }  // namespace internal
 }  // namespace ash