Added CommandBufferClient, CommandBufferStub and some IPC messages....

gpu/command_buffer/service/common_decoder.cc

Index: gpu/command_buffer/service/common_decoder.cc
===================================================================
--- gpu/command_buffer/service/common_decoder.cc	(revision 34314)
+++ gpu/command_buffer/service/common_decoder.cc	(working copy)
@@ -33,7 +33,7 @@
 #include "gpu/command_buffer/service/common_decoder.h"
 #include "gpu/command_buffer/service/cmd_buffer_engine.h"
 
-namespace command_buffer {
+namespace gpu {
 
 const void* CommonDecoder::Bucket::GetData(size_t offset, size_t size) const {
   if (OffsetSizeValid(offset, size)) {
@@ -295,4 +295,4 @@
   return parse_error::kParseNoError;
 }
 
-}  // namespace command_buffer
+}  // namespace gpu