Move Insert/SignalSyncPoint() to GpuControl

ppapi/proxy/ppapi_command_buffer_proxy.cc

Index: ppapi/proxy/ppapi_command_buffer_proxy.cc
diff --git a/ppapi/proxy/ppapi_command_buffer_proxy.cc b/ppapi/proxy/ppapi_command_buffer_proxy.cc
index ccb3a045968a73310de4f9020e1ca803a4cbec4e..b224f173c146932856cfb981c35f49025dc2d292 100644
--- a/ppapi/proxy/ppapi_command_buffer_proxy.cc
+++ b/ppapi/proxy/ppapi_command_buffer_proxy.cc
@@ -203,6 +203,11 @@ uint32 PpapiCommandBufferProxy::InsertSyncPoint() {
   return sync_point;
 }
 
+void PpapiCommandBufferProxy::SignalSyncPoint(uint32 sync_point,
+                                              const base::Closure& callback) {
+  NOTREACHED();
+}
+
 bool PpapiCommandBufferProxy::SupportsGpuMemoryBuffer() {
   return false;
 }