Move capture scheduling logic from VideoScheduler to CaptureScheduler.

remoting/host/capture_scheduler.h

Index: remoting/host/capture_scheduler.h
diff --git a/remoting/host/capture_scheduler.h b/remoting/host/capture_scheduler.h
index 9dbecdad3d14720167cf321977f45c46afa4a618..610b35ba490b9cb1ef4b5bcedbde46bd6d28c624 100644
--- a/remoting/host/capture_scheduler.h
+++ b/remoting/host/capture_scheduler.h
@@ -9,38 +9,83 @@
 #ifndef REMOTING_HOST_CAPTURE_SCHEDULER_H_
 #define REMOTING_HOST_CAPTURE_SCHEDULER_H_
 
+#include "base/callback.h"
+#include "base/threading/non_thread_safe.h"
+#include "base/time/tick_clock.h"
 #include "base/time/time.h"
+#include "base/timer/timer.h"
 #include "remoting/base/running_average.h"
 
 namespace remoting {
 
-class CaptureScheduler {
+// CaptureScheduler is used by the VideoScheduler to scheduler frame capturer,
+// taking into account capture delay, encoder delay, network bandwidth, etc.
+class CaptureScheduler : public base::NonThreadSafe {
  public:
-  CaptureScheduler();
+  explicit CaptureScheduler(const base::Closure& capture_closure);
   ~CaptureScheduler();
 
-  // Returns the time to wait after initiating a capture before triggering
-  // the next.
-  base::TimeDelta NextCaptureDelay();
+  // Starts the scheduler.
+  void Start();
 
-  // Records time spent on capturing and encoding.
-  void RecordCaptureTime(base::TimeDelta capture_time);
-  void RecordEncodeTime(base::TimeDelta encode_time);
+  // Pauses or unpauses the stream.
+  void Pause(bool pause);
+
+  // Notifies the scheduler that a capture has been completed.
+  void OnCaptureCompleted();
+
+  // Notifies the scheduler than a frame has been encoded.
+  void OnFrameEncoded(base::TimeDelta encode_time);
+
+  // Notifies the scheduler than a frame has been sent.
+  void OnFrameSent();
 
   // Sets minimum interval between frames.
   void set_minimum_interval(base::TimeDelta minimum_interval) {
     minimum_interval_ = minimum_interval;
   }
 
-  // Overrides the number of processors for testing.
-  void SetNumOfProcessorsForTest(int num_of_processors);
+  // Helper functions for tests.
+  void set_tick_clock_for_tests(scoped_ptr<base::TickClock> tick_clock) {
+    tick_clock_ = tick_clock.Pass();
+  }
+  void set_timer_for_tests(scoped_ptr<base::Timer> timer) {
+    capture_timer_ = timer.Pass();
+  }
+  void set_num_of_processors_for_tests(int num_of_processors) {
+    num_of_processors_ = num_of_processors;
+  }
 
  private:
+  // Schedules |capture_timer_| to call CaptureNextFrame() at appropriate time.
+  // Doesn't do anything if next frame cannot be captured yet (e.g. because
+  // there are too many frames being processed).
+  void ScheduleNextCapture();
+
+  // Called by |capture_timer_|. Calls |capture_closure_| to start capturing a
+  // new frame.
+  void CaptureNextFrame();
+
+  base::Closure capture_closure_;
+
+  scoped_ptr<base::TickClock> tick_clock_;

[Wez, 2015/02/02 21:40:48]

tick_clock_for_tests_?

[Sergey Ulanov, 2015/02/03 23:49:52]

I don't think that would be appropriate name for it because it's called from
production code (it can be changed from non-default value only in tests though)

+
+  // Timer used to schedule CaptureNextFrame().
+  scoped_ptr<base::Timer> capture_timer_;
+
+  // Minimum interval between frames.
   base::TimeDelta minimum_interval_;
+
   int num_of_processors_;
+
   RunningAverage capture_time_;
   RunningAverage encode_time_;
 
+  int pending_frames_;
+  bool capture_pending_;
+  base::TimeTicks last_capture_started_time_;
+  bool is_paused_;
+
   DISALLOW_COPY_AND_ASSIGN(CaptureScheduler);
 };