gpu: Refactor GpuMemoryBuffer framework for multi-process support.

gpu/command_buffer/service/common_decoder_unittest.cc

Index: gpu/command_buffer/service/common_decoder_unittest.cc
diff --git a/gpu/command_buffer/service/common_decoder_unittest.cc b/gpu/command_buffer/service/common_decoder_unittest.cc
index d90e34bf93bbd4c547c19e2d45052a2200f90131..76b4dc5968341a55968b9e1f2427df119a270356 100644
--- a/gpu/command_buffer/service/common_decoder_unittest.cc
+++ b/gpu/command_buffer/service/common_decoder_unittest.cc
@@ -135,6 +135,12 @@ class MockCommandBufferEngine : public CommandBufferEngine {
     return get_offset_;
   }
 
+  // Overridden from CommandBufferEngine.
+  virtual gfx::GLImage* GetImage(int32 image_id) OVERRIDE {
+    NOTREACHED();
+    return NULL;
+  }
+
  private:
   bool IsValidSharedMemoryId(int32 shm_id) {
     return shm_id == kValidShmId || shm_id == kStartValidShmId;