[Video] Disable bg optimization if avg keyframe distance is >10s

media/blink/webmediaplayer_impl.h

Index: media/blink/webmediaplayer_impl.h
diff --git a/media/blink/webmediaplayer_impl.h b/media/blink/webmediaplayer_impl.h
index 225bc0adac125f15a3ba3df01d6d46d4240e7f9a..fcc69775df8af737f311b1e73567b64241c1afc3 100644
--- a/media/blink/webmediaplayer_impl.h
+++ b/media/blink/webmediaplayer_impl.h
@@ -19,6 +19,7 @@
 #include "base/memory/weak_ptr.h"
 #include "base/threading/thread.h"
 #include "base/time/default_tick_clock.h"
+#include "base/time/time.h"
 #include "base/timer/elapsed_timer.h"
 #include "base/timer/timer.h"
 #include "build/build_config.h"
@@ -620,6 +621,12 @@ class MEDIA_BLINK_EXPORT WebMediaPlayerImpl
   // Whether the player is currently in autoplay muted state.
   bool autoplay_muted_ = false;
 
+  // The maximum video keyframe distance that allows triggering background
+  // playback optimizations.
+  // 10 seconds by default but can be overridden by a Finch experiment.

[DaleCurtis, 2017/01/10 21:11:40]

This statement isn't true at the moment? Are you sure you can override the value
via Finch config? I thought you could only select from predefined values.

[whywhat, 2017/01/10 21:51:54]

I was advised to use GetVariationParamValueByFeature()
(https://cs.chromium.org/chromium/src/components/variations/variations_associa...)
by the Finch team.

Not true at the moment though.

+  base::TimeDelta max_keyframe_distance_for_fast_decode_ =
+      base::TimeDelta::FromSeconds(10);
+
   // Whether disabled the video track as an optimization.
   bool video_track_disabled_ = false;