Gets Bubble to work on aura.

ui/gfx/compositor/layer.cc

 // Copyright (c) 2011 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 "ui/gfx/compositor/layer.h"
 
 #include <algorithm>
 
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
@@ skipping 596 matching lines @@
 void Layer::SetTransformImmediately(const ui::Transform& transform) {
   transform_ = transform;
 
   SetNeedsToRecomputeHole();
 #if defined(USE_WEBKIT_COMPOSITOR)
   RecomputeTransform();
 #endif
 }
 
 void Layer::SetOpacityImmediately(float opacity) {
+  bool schedule_draw = (opacity != opacity_ && IsDrawn());
   opacity_ = opacity;
   SetNeedsToRecomputeHole();
 #if defined(USE_WEBKIT_COMPOSITOR)
   if (visible_)
     web_layer_.setOpacity(opacity);
 #endif
+  if (schedule_draw)
+    ScheduleDraw();
 }
 
 void Layer::SetBoundsFromAnimation(const gfx::Rect& bounds) {
   SetBoundsImmediately(bounds);
 }
 
 void Layer::SetTransformFromAnimation(const Transform& transform) {
   SetTransformImmediately(transform);
 }
 
@@ skipping 51 matching lines @@
 #else
     unsigned int texture_id = 0;
 #endif
     web_layer_.to<WebKit::WebExternalTextureLayer>().setTextureId(
         should_draw ? texture_id : 0);
   }
 }
 #endif
 
 }  // namespace ui