Revert 113479 - Revert "Revert 113250 - Add CommandBuffer::SetGetBuffer"

gpu/command_buffer/common/command_buffer.h

 // Copyright (c) 2011 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_COMMON_COMMAND_BUFFER_H_
 #define GPU_COMMAND_BUFFER_COMMON_COMMAND_BUFFER_H_
 
 #include "../common/buffer.h"
 #include "../common/constants.h"
 
@@ skipping 49 matching lines @@
     uint32 generation;
   };
 
   CommandBuffer() {
   }
 
   virtual ~CommandBuffer() {
   }
 
   // Initialize the command buffer with the given size.
-  virtual bool Initialize() = 0;
+  virtual bool Initialize(int32 size) = 0;
+
+  // Initialize the command buffer using the given preallocated buffer.
+  virtual bool Initialize(base::SharedMemory* buffer, int32 size) = 0;
+
+  // Gets the ring buffer for the command buffer.
+  virtual Buffer GetRingBuffer() = 0;
 
   // Returns the current status.
   virtual State GetState() = 0;
 
   // Returns the last state without synchronizing with the service.
   virtual State GetLastState() = 0;
 
   // The writer calls this to update its put offset. This ensures the reader
   // sees the latest added commands, and will eventually process them. On the
   // service side, commands are processed up to the given put_offset before
   // subsequent Flushes on the same GpuChannel.
   virtual void Flush(int32 put_offset) = 0;
 
   // The writer calls this to update its put offset. This function returns the
   // reader's most recent get offset. Does not return until all pending commands
   // have been executed.
   virtual State FlushSync(int32 put_offset, int32 last_known_get) = 0;
 
-  // Sets the buffer commands are read from.
-  // Also resets the get and put offsets to 0.
-  virtual void SetGetBuffer(int32 transfer_buffer_id) = 0;
-
   // Sets the current get offset. This can be called from any thread.
   virtual void SetGetOffset(int32 get_offset) = 0;
 
   // Create a transfer buffer and return a handle that uniquely
   // identifies it or -1 on error. id_request lets the caller request a
   // specific id for the transfer buffer, or -1 if the caller does not care.
   // If the requested id can not be fulfilled, a different id will be returned.
   // id_request must be either -1 or between 0 and 100.
   virtual int32 CreateTransferBuffer(size_t size, int32 id_request) = 0;
 
@@ skipping 24 matching lines @@
   // call this first.
   virtual void SetContextLostReason(error::ContextLostReason) = 0;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(CommandBuffer);
 };
 
 }  // namespace gpu
 
 #endif  // GPU_COMMAND_BUFFER_COMMON_COMMAND_BUFFER_H_