[scheduler] Add WakeupBudgetPool.

third_party/WebKit/Source/platform/scheduler/base/task_queue.h

Index: third_party/WebKit/Source/platform/scheduler/base/task_queue.h
diff --git a/third_party/WebKit/Source/platform/scheduler/base/task_queue.h b/third_party/WebKit/Source/platform/scheduler/base/task_queue.h
index de227cc40f376a60f8b96c724160cf3e6c9f7efa..5be3196e235ffb73eba1b3e0ccba78a821f69eea 100644
--- a/third_party/WebKit/Source/platform/scheduler/base/task_queue.h
+++ b/third_party/WebKit/Source/platform/scheduler/base/task_queue.h
@@ -220,6 +220,9 @@ class BLINK_PLATFORM_EXPORT TaskQueue : public base::SingleThreadTaskRunner {
   // blocked by it.
   virtual void RemoveFence() = 0;
 
+  virtual bool HasFence() const = 0;
+
+  // Returns true if the queue has a fence which is blocking execution of tasks.
   virtual bool BlockedByFence() const = 0;
 
   virtual void SetObserver(Observer* observer) = 0;