Remove the Views bubble double widget hack.

ui/views/bubble/bubble_border.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 "ui/views/bubble/bubble_border.h"
 
 #include <algorithm>
 
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
@@ skipping 336 matching lines @@
   paint.setStyle(SkPaint::kFill_Style);
   paint.setColor(background_color_);
 
   canvas->DrawPath(path, paint);
 }
 
 void BubbleBackground::Paint(gfx::Canvas* canvas, views::View* view) const {
   if (border_->shadow() == BubbleBorder::NO_SHADOW_OPAQUE_BORDER)
     canvas->DrawColor(border_->background_color());
 
-  // Clip out the client bounds to prevent overlapping transparent widgets.
-  if (!border_->client_bounds().IsEmpty()) {
-    SkRect client_rect(gfx::RectToSkRect(border_->client_bounds()));
-    canvas->sk_canvas()->clipRect(client_rect, SkRegion::kDifference_Op);
-  }
-
   // Fill the contents with a round-rect region to match the border images.
   SkPaint paint;
   paint.setAntiAlias(true);
   paint.setStyle(SkPaint::kFill_Style);
   paint.setColor(border_->background_color());
   SkPath path;
   gfx::Rect bounds(view->GetLocalBounds());
   bounds.Inset(border_->GetInsets());
 
   SkScalar radius = SkIntToScalar(border_->GetBorderCornerRadius());
   path.addRoundRect(gfx::RectToSkRect(bounds), radius, radius);
   canvas->DrawPath(path, paint);
 }
 
 }  // namespace views