gpu: Implement idle async pixel transfers.

gpu/command_buffer/service/gpu_scheduler.cc

Index: gpu/command_buffer/service/gpu_scheduler.cc
diff --git a/gpu/command_buffer/service/gpu_scheduler.cc b/gpu/command_buffer/service/gpu_scheduler.cc
index 61bdcf8470e652631741885edcef724f8f94fb81..0280dc8e9aa19b04ed4aeba0411a1c99f885a907 100644
--- a/gpu/command_buffer/service/gpu_scheduler.cc
+++ b/gpu/command_buffer/service/gpu_scheduler.cc
@@ -167,8 +167,7 @@ bool GpuScheduler::IsScheduled() {
 }
 
 bool GpuScheduler::HasMoreWork() {
-  return !unschedule_fences_.empty() ||
-         (decoder_ && decoder_->ProcessPendingQueries());
+  return !unschedule_fences_.empty() || (decoder_ && decoder_->HasMoreWork());
 }
 
 void GpuScheduler::SetSchedulingChangedCallback(
@@ -269,6 +268,10 @@ bool GpuScheduler::IsPreempted() {
   return preemption_flag_->IsSet();
 }
 
+bool GpuScheduler::PerformIdleWork() {
+  return (decoder_ && decoder_->PerformIdleWork());
+}
+
 void GpuScheduler::RescheduleTimeOut() {
   int new_count = unscheduled_count_ + rescheduled_count_;