GPU: Build most of the gpu as a single DLL.

gpu/command_buffer/service/command_buffer_service.h

Index: gpu/command_buffer/service/command_buffer_service.h
===================================================================
--- gpu/command_buffer/service/command_buffer_service.h	(revision 124716)
+++ gpu/command_buffer/service/command_buffer_service.h	(working copy)
@@ -19,7 +19,7 @@
 
 // An object that implements a shared memory command buffer and a synchronous
 // API to manage the put and get pointers.
-class CommandBufferService : public CommandBuffer {
+class GPU_EXPORT CommandBufferService : public CommandBuffer {
  public:
   typedef base::Callback<bool(int32)> GetBufferChangedCallback;
   CommandBufferService();