[scheduler]: Avoid waking up the scheduler to end long idle periods.

components/scheduler/renderer/renderer_scheduler_impl.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef COMPONENTS_SCHEDULER_RENDERER_RENDERER_SCHEDULER_IMPL_H_
 #define COMPONENTS_SCHEDULER_RENDERER_RENDERER_SCHEDULER_IMPL_H_
 
 #include "base/atomicops.h"
 #include "base/synchronization/lock.h"
 #include "components/scheduler/child/idle_helper.h"
+#include "components/scheduler/child/pollable_thread_safe_flag.h"
 #include "components/scheduler/child/scheduler_helper.h"
 #include "components/scheduler/renderer/deadline_task_runner.h"
 #include "components/scheduler/renderer/renderer_scheduler.h"
 #include "components/scheduler/scheduler_export.h"
 
 namespace base {
 namespace trace_event {
 class ConvertableToTraceFormat;
 }
 }
@@ skipping 63 matching lines @@
   // enum.
   enum class InputStreamState {
     INACTIVE,
     ACTIVE,
     ACTIVE_AND_AWAITING_TOUCHSTART_RESPONSE,
     // Must be the last entry.
     INPUT_STREAM_STATE_COUNT,
     FIRST_INPUT_STREAM_STATE = INACTIVE,
   };
 
-  class PollableNeedsUpdateFlag {
-   public:
-    PollableNeedsUpdateFlag(base::Lock* write_lock);
-    ~PollableNeedsUpdateFlag();
-
-    // Set the flag. May only be called if |write_lock| is held.
-    void SetWhileLocked(bool value);
-
-    // Returns true iff the flag is set to true.
-    bool IsSet() const;
-
-   private:
-    base::subtle::Atomic32 flag_;
-    base::Lock* write_lock_;  // Not owned.
-
-    DISALLOW_COPY_AND_ASSIGN(PollableNeedsUpdateFlag);
-  };
-
   // IdleHelper::Delegate implementation:
   bool CanEnterLongIdlePeriod(
       base::TimeTicks now,
       base::TimeDelta* next_long_idle_period_delay_out) override;
   void IsNotQuiescent() override {}
 
   void EndIdlePeriod();
 
   // Returns the serialized scheduler state for tracing.
   scoped_refptr<base::trace_event::ConvertableToTraceFormat> AsValue(
@@ skipping 83 matching lines @@
 
   base::TimeTicks estimated_next_frame_begin_;
 
   // The incoming_signals_lock_ mutex protects access to all variables in the
   // (contiguous) block below.
   mutable base::Lock incoming_signals_lock_;
   base::TimeTicks last_input_receipt_time_on_compositor_;
   base::TimeTicks last_input_process_time_on_main_;
   blink::WebInputEvent::Type last_input_type_;
   InputStreamState input_stream_state_;
-  PollableNeedsUpdateFlag policy_may_need_update_;
+  PollableThreadSafeFlag policy_may_need_update_;
   int timer_queue_suspend_count_;  // TIMER_TASK_QUEUE suspended if non-zero.
 
   base::WeakPtrFactory<RendererSchedulerImpl> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(RendererSchedulerImpl);
 };
 
 }  // namespace scheduler
 
 #endif  // COMPONENTS_SCHEDULER_RENDERER_RENDERER_SCHEDULER_IMPL_H_