mash: Close the system tray bubble on click outside its bounds

ash/system/tray/system_tray.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/system/tray/system_tray.h"
 
 #include "ash/ash_switches.h"
 #include "ash/metrics/user_metrics_recorder.h"
 #include "ash/shelf/shelf_layout_manager.h"
 #include "ash/shelf/shelf_util.h"
@@ skipping 635 matching lines @@
   if (system_bubble_.get() && bubble_view == system_bubble_->bubble_view()) {
     DestroySystemBubble();
     UpdateNotificationBubble();  // State changed, re-create notifications.
     GetShelfLayoutManager()->UpdateAutoHideState();
   } else if (notification_bubble_.get() &&
              bubble_view == notification_bubble_->bubble_view()) {
     DestroyNotificationBubble();
   }
 }
 
-bool SystemTray::ClickedOutsideBubble() {
+void SystemTray::ClickedOutsideBubble() {
   if (!system_bubble_ || system_bubble_->is_persistent())
-    return false;
+    return;
   HideBubbleWithView(system_bubble_->bubble_view());
-  return true;
 }
 
 void SystemTray::BubbleViewDestroyed() {
   if (system_bubble_) {
     system_bubble_->bubble()->DestroyItemViews();
     system_bubble_->bubble()->BubbleViewDestroyed();
   }
 }
 
 void SystemTray::OnMouseEnteredView() {
@@ skipping 56 matching lines @@
   system_bubble_.reset();
   // When closing a system bubble with the alternate shelf layout, we need to
   // turn off the active tinting of the shelf.
   if (full_system_tray_menu_) {
     SetDrawBackgroundAsActive(false);
     full_system_tray_menu_ = false;
   }
 }
 
 }  // namespace ash