cc: Make cc_unittests opt into real GL NullDraw contexts.

cc/test/pixel_test.h

 // Copyright 2013 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/file_util.h"
 #include "cc/output/gl_renderer.h"
 #include "cc/output/software_renderer.h"
 #include "cc/quads/render_pass.h"
 #include "cc/test/pixel_comparator.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "ui/gfx/size.h"
+#include "ui/gl/gl_implementation.h"
 
 #ifndef CC_TEST_PIXEL_TEST_H_
 #define CC_TEST_PIXEL_TEST_H_
 
 namespace cc {
 class CopyOutputResult;
 class DirectRenderer;
 class FakeOutputSurfaceClient;
 class OutputSurface;
 class ResourceProvider;
@@ skipping 44 matching lines @@
 
   // RendererClient implementation.
   virtual void SetFullRootLayerDamage() OVERRIDE {}
 
  private:
   void ReadbackResult(base::Closure quit_run_loop,
                       scoped_ptr<CopyOutputResult> result);
 
   bool PixelsMatchReference(const base::FilePath& ref_file,
                             const PixelComparator& comparator);
+
+  scoped_ptr<gfx::DisableNullDrawGLBindings> enable_pixel_output_;
 };
 
 template<typename RendererType>
 class RendererPixelTest : public PixelTest {
  public:
   RendererType* renderer() {
     return static_cast<RendererType*>(renderer_.get());
   }
 
   bool UseSkiaGPUBackend() const;
@@ skipping 97 matching lines @@
     SoftwareRendererWithExpandedViewport>::ExpandedViewport() const {
   return true;
 }
 
 typedef RendererPixelTest<GLRenderer> GLRendererPixelTest;
 typedef RendererPixelTest<SoftwareRenderer> SoftwareRendererPixelTest;
 
 }  // namespace cc
 
 #endif  // CC_TEST_PIXEL_TEST_H_