Fix a bug in the implementation of DescheduleUntilFinishedCHROMIUM.

gpu/command_buffer/service/command_executor.cc

Index: gpu/command_buffer/service/command_executor.cc
diff --git a/gpu/command_buffer/service/command_executor.cc b/gpu/command_buffer/service/command_executor.cc
index f541a537f80988bd0f5fef37e08d4b6bcaa41418..ff7a910bf86a8263b70eae0440746003f5295e2b 100644
--- a/gpu/command_buffer/service/command_executor.cc
+++ b/gpu/command_buffer/service/command_executor.cc
@@ -177,4 +177,14 @@ void CommandExecutor::PerformIdleWork() {
   decoder_->PerformIdleWork();
 }
 
+bool CommandExecutor::HasPollingWork() const {
+  return (decoder_ && decoder_->HasPollingWork());
+}
+
+void CommandExecutor::PerformPollingWork() {
+  if (!decoder_)
+    return;
+  decoder_->PerformPollingWork();
+}
+
 }  // namespace gpu