TabCapture: enforce active refresh if there is un-sampled compositor update

media/capture/content/video_capture_oracle.h

 // Copyright (c) 2013 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 MEDIA_CAPTURE_CONTENT_VIDEO_CAPTURE_ORACLE_H_
 #define MEDIA_CAPTURE_CONTENT_VIDEO_CAPTURE_ORACLE_H_
 
 #include "base/callback_forward.h"
 #include "base/time/time.h"
 #include "media/base/feedback_signal_accumulator.h"
@@ skipping 127 matching lines @@
   // size in response to end-to-end utilization.
   const bool auto_throttling_enabled_;
 
   // Incremented every time a paint or update event occurs.
   int next_frame_number_;
 
   // Stores the last |event_time| from the last observation/decision.  Used to
   // sanity-check that event times are monotonically non-decreasing.
   base::TimeTicks last_event_time_[kNumEvents];
 
+  // Set to true if there have been updates to the source content that were not
+  // sampled. This will prevent passive refresh requests from being satisfied
+  // when an active refresh should be used instead.
+  bool source_is_dirty_;
+
+  // The last |event| passed to ObserveEventAndDecideCapture() where it returned
+  // a "yes" decision. This is used by RecordCapture() to decide whether the
+  // |source_is_dirty_| flag can be cleared.
+  Event last_event_causing_capture_;

[miu, 2017/03/24 21:17:28]

Per discussion, we don't need |last_event_causing_capture_| anymore (since a
RecordCapture() call always means the dirty flag can be cleared).

[braveyao, 2017/03/24 23:12:27]

Done.

+
   // Updated by the last call to ObserveEventAndDecideCapture() with the
   // estimated duration of the next frame to sample.  This is zero if the method
   // returned false.
   base::TimeDelta duration_of_next_frame_;
 
   // Stores the frame number from the last successfully delivered frame.
   int last_successfully_delivered_frame_number_;
 
   // Stores the number of pending frame captures.
   int num_frames_pending_;
@@ skipping 40 matching lines @@
 
   // The timestamp of the frame where |content_sampler_| last detected
   // animation.  This determines whether capture size increases will be
   // aggressive (because content is not animating).
   base::TimeTicks last_time_animation_was_detected_;
 };
 
 }  // namespace media
 
 #endif  // MEDIA_CAPTURE_CONTENT_VIDEO_CAPTURE_ORACLE_H_