gpu: Reuse transfer buffers more aggresively

gpu/command_buffer/service/command_buffer_service.cc

Index: gpu/command_buffer/service/command_buffer_service.cc
diff --git a/gpu/command_buffer/service/command_buffer_service.cc b/gpu/command_buffer/service/command_buffer_service.cc
index bae2d801dd5021612ce6550bdcd7197c10082c72..7409e99e93cec2eecf3b1c0b34fd8917943009b9 100644
--- a/gpu/command_buffer/service/command_buffer_service.cc
+++ b/gpu/command_buffer/service/command_buffer_service.cc
@@ -25,6 +25,7 @@ CommandBufferService::CommandBufferService(
       put_offset_(0),
       transfer_buffer_manager_(transfer_buffer_manager),
       token_(0),
+      serial_(0),
       generation_(0),
       error_(error::kNoError),
       context_lost_reason_(error::kUnknown) {
@@ -43,6 +44,7 @@ CommandBufferService::State CommandBufferService::GetState() {
   state.get_offset = get_offset_;
   state.put_offset = put_offset_;
   state.token = token_;
+  state.serial = serial_;
   state.error = error_;
   state.context_lost_reason = context_lost_reason_;
   state.generation = ++generation_;
@@ -174,6 +176,11 @@ void CommandBufferService::SetToken(int32 token) {
   UpdateState();
 }
 
+void CommandBufferService::SetSerial(uint32 serial) {
+  serial_ = serial;
+  UpdateState();
+}
+
 void CommandBufferService::SetParseError(error::Error error) {
   if (error_ == error::kNoError) {
     error_ = error;