aura: Use Layer::SetShowPaintedContent to stop showing external content

ui/aura/bench/bench_main.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 "base/at_exit.h"
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/i18n/icu_util.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/message_loop/message_loop.h"
@@ skipping 209 matching lines @@
         GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0,
         GL_TEXTURE_2D, texture_->PrepareTexture(), 0);
     context->clearColor(0.f, 1.f, 0.f, 1.f);
     context->clear(GL_COLOR_BUFFER_BIT);
     context->flush();
   }
 
   virtual ~WebGLBench() {
     context_provider_->Context3d()->makeContextCurrent();
     context_provider_->Context3d()->deleteFramebuffer(fbo_);
-    webgl_.SetExternalTexture(NULL);
+    webgl_.SetShowPaintedContent();
     texture_ = NULL;
     compositor_->RemoveObserver(this);
   }
 
   virtual void Draw() OVERRIDE {
     if (do_draw_) {
       WebKit::WebGraphicsContext3D* context = context_provider_->Context3d();
       context->makeContextCurrent();
       context->clearColor((frames() % kFrames)*1.0/kFrames, 1.f, 0.f, 1.f);
       context->clear(GL_COLOR_BUFFER_BIT);
@@ skipping 120 matching lines @@
   ui::PrintLayerHierarchy(root_window->layer(), gfx::Point(100, 100));
 #endif
 
   root_window->ShowRootWindow();
   base::MessageLoopForUI::current()->Run();
   focus_client.reset();
   root_window.reset();
 
   return 0;
 }