Fix preserve backbuffer with native GMBs.

gpu/command_buffer/tests/gl_manager.h

 // 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.
 
 #ifndef GPU_COMMAND_BUFFER_TESTS_GL_MANAGER_H_
 #define GPU_COMMAND_BUFFER_TESTS_GL_MANAGER_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 64 matching lines @@
     bool context_lost_allowed;
     gles2::ContextType context_type;
     // Force shader name hashing for all context types.
     bool force_shader_name_hashing;
     // Whether the buffer is multisampled.
     bool multisampled;
     // Whether the backbuffer has an alpha channel.
     bool backbuffer_alpha;
     // The ImageFactory to use to generate images for the backbuffer.
     gpu::ImageFactory* image_factory;
+    // Whether to preserve the backbuffer after a call to SwapBuffers().
+    bool preserve_backbuffer;
   };
   GLManager();
   ~GLManager() override;
 
   std::unique_ptr<gfx::GpuMemoryBuffer> CreateGpuMemoryBuffer(
       const gfx::Size& size,
       gfx::BufferFormat format);
 
   void Initialize(const Options& options);
   void InitializeWithCommandLine(const Options& options,
@@ skipping 93 matching lines @@
   // Used on Android to virtualize GL for all contexts.
   static int use_count_;
   static scoped_refptr<gl::GLShareGroup>* base_share_group_;
   static scoped_refptr<gl::GLSurface>* base_surface_;
   static scoped_refptr<gl::GLContext>* base_context_;
 };
 
 }  // namespace gpu
 
 #endif  // GPU_COMMAND_BUFFER_TESTS_GL_MANAGER_H_