Use a single ToplevelWindowEventHandler for the ash::Shell

ash/wm/workspace/workspace_event_handler.cc

Index: ash/wm/workspace/workspace_event_handler.cc
diff --git a/ash/wm/workspace/workspace_event_handler.cc b/ash/wm/workspace/workspace_event_handler.cc
index 2723bea1ef5c199bc661df13b4ac3eb7185bbbf1..e931b4ac701cddc1ef060efb33c231863404763b 100644
--- a/ash/wm/workspace/workspace_event_handler.cc
+++ b/ash/wm/workspace/workspace_event_handler.cc
@@ -54,14 +54,10 @@ void ToggleMaximizedState(wm::WindowState* window_state) {
 
 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) {
@@ -82,23 +78,17 @@ void WorkspaceEventHandler::OnMouseEvent(ui::MouseEvent* event) {
     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);
@@ -107,7 +97,6 @@ void WorkspaceEventHandler::OnMouseEvent(ui::MouseEvent* event) {
     default:
       break;
   }
-  ToplevelWindowEventHandler::OnMouseEvent(event);
 }
 
 void WorkspaceEventHandler::OnGestureEvent(ui::GestureEvent* event) {
@@ -122,7 +111,6 @@ void WorkspaceEventHandler::OnGestureEvent(ui::GestureEvent* event) {
       // 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;
@@ -132,7 +120,6 @@ void WorkspaceEventHandler::OnGestureEvent(ui::GestureEvent* event) {
           TouchUMA::GESTURE_FRAMEVIEW_TAP);
     }
   }
-  ToplevelWindowEventHandler::OnGestureEvent(event);
 }
 
 void WorkspaceEventHandler::HandleVerticalResizeDoubleClick(
@@ -154,6 +141,7 @@ void WorkspaceEventHandler::HandleVerticalResizeDoubleClick(
            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);
@@ -162,6 +150,7 @@ void WorkspaceEventHandler::HandleVerticalResizeDoubleClick(
                                      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.
@@ -172,6 +161,7 @@ void WorkspaceEventHandler::HandleVerticalResizeDoubleClick(
            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);
@@ -180,6 +170,7 @@ void WorkspaceEventHandler::HandleVerticalResizeDoubleClick(
                                      origin.y(),
                                      work_area.width(),
                                      target->bounds().height()));
+        event->StopPropagation();
       }
     }
   }