Refactor gpu::Buffer to allow different types of backing

gpu/command_buffer/client/mapped_memory_unittest.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 "gpu/command_buffer/client/mapped_memory.h"
 
 #include <list>
 #include "base/bind.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/message_loop/message_loop.h"
@@ skipping 84 matching lines @@
 // CommandBufferHelper with a mock AsyncAPIInterface for its interface (calling
 // it directly, not through the RPC mechanism), making sure Noops are ignored
 // and SetToken are properly forwarded to the engine.
 class MemoryChunkTest : public MappedMemoryTestBase {
  protected:
   static const int32 kShmId = 123;
   virtual void SetUp() {
     MappedMemoryTestBase::SetUp();
     scoped_ptr<base::SharedMemory> shared_memory(new base::SharedMemory());
     shared_memory->CreateAndMapAnonymous(kBufferSize);
-    buffer_ = new gpu::Buffer(shared_memory.Pass(), kBufferSize);
+    buffer_ = MakeBufferFromSharedMemory(shared_memory.Pass(), kBufferSize);
     chunk_.reset(new MemoryChunk(kShmId,
                                  buffer_,
                                  helper_.get(),
                                  base::Bind(&EmptyPoll)));
   }
 
   virtual void TearDown() {
     // If the GpuScheduler posts any tasks, this forces them to run.
     base::MessageLoop::current()->RunUntilIdle();
 
@@ skipping 331 matching lines @@
   unsigned int offset3;
   void* mem3 = manager_->Alloc(kSize, &id3, &offset3);
   EXPECT_EQ(manager_->bytes_in_use(), kSize * 2);
 
   manager_->Free(mem2);
   manager_->Free(mem3);
   EXPECT_EQ(manager_->bytes_in_use(), static_cast<size_t>(0));
 }
 
 }  // namespace gpu