[scheduler] Add WakeupBudgetPool.

third_party/WebKit/Source/platform/scheduler/base/task_queue_impl.cc

Index: third_party/WebKit/Source/platform/scheduler/base/task_queue_impl.cc
diff --git a/third_party/WebKit/Source/platform/scheduler/base/task_queue_impl.cc b/third_party/WebKit/Source/platform/scheduler/base/task_queue_impl.cc
index bd60d62149c64dcea7743c4446643f4d07c3666f..f1b91ea06654e24823693a94781121af70ec5b74 100644
--- a/third_party/WebKit/Source/platform/scheduler/base/task_queue_impl.cc
+++ b/third_party/WebKit/Source/platform/scheduler/base/task_queue_impl.cc
@@ -691,6 +691,10 @@ bool TaskQueueImpl::BlockedByFence() const {
          main_thread_only().current_fence;
 }
 
+bool TaskQueueImpl::HasFence() const {
+  return !!main_thread_only().current_fence;
+}
+
 bool TaskQueueImpl::CouldTaskRun(EnqueueOrder enqueue_order) const {
   if (!IsQueueEnabled())
     return false;