More flexibility in BubbleBorder arrow rendering.

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/shell.h"
 #include "ash/shell/panel_window.h"
 #include "ash/shell_window_ids.h"
@@ skipping 357 matching lines @@
       // This is the case where a volume control or brightness control bubble
       // is created.
       init_params.max_height = default_bubble_height_;
       init_params.arrow_color = kBackgroundColor;
     } else {
       init_params.arrow_color = kHeaderBackgroundColor;
     }
     init_params.arrow_offset = arrow_offset;
     // For Volume and Brightness we don't want to show an arrow when
     // they are shown in a bubble by themselves.
-    init_params.hide_arrow = items.size() == 1 && items[0]->ShouldHideArrow();
+    init_params.arrow_paint_type = views::BubbleBorder::PAINT_NORMAL;
+    if (items.size() == 1 && items[0]->ShouldHideArrow())
+      init_params.arrow_paint_type = views::BubbleBorder::PAINT_TRANSPARENT;
     SystemTrayBubble* bubble = new SystemTrayBubble(this, items, bubble_type);
     system_bubble_.reset(new internal::SystemBubbleWrapper(bubble));
     system_bubble_->InitView(this, tray_container(), &init_params);
   }
   // Save height of default view for creating detailed views directly.
   if (!detailed)
     default_bubble_height_ = system_bubble_->bubble_view()->height();
 
   if (detailed && items.size() > 0)
     detailed_item_ = items[0];
@@ skipping 143 matching lines @@
         ConvertPointToWidget(this, &point);
         arrow_offset = point.x();
       }
     }
     ShowDefaultViewWithOffset(BUBBLE_CREATE_NEW, arrow_offset);
   }
   return true;
 }
 
 }  // namespace ash