Request keyframe if too many packets are missing and NACK is disabled.

webrtc/modules/video_coding/main/source/jitter_buffer.h

Index: webrtc/modules/video_coding/main/source/jitter_buffer.h
diff --git a/webrtc/modules/video_coding/main/source/jitter_buffer.h b/webrtc/modules/video_coding/main/source/jitter_buffer.h
index 3961dff46ffaffb2d15fbb568fc311f6a46814cc..af619adc7c8bcf797e3dbe76fb2ae9ad8d380bcd 100644
--- a/webrtc/modules/video_coding/main/source/jitter_buffer.h
+++ b/webrtc/modules/video_coding/main/source/jitter_buffer.h
@@ -206,13 +206,15 @@ class VCMJitterBuffer {
       EXCLUSIVE_LOCKS_REQUIRED(crit_sect_);
 
   // Returns true if |frame| is continuous in |decoding_state|, not taking
-  // decodable frames into account.
+  // decodable frames into account and optionally ignoring |decode_error_mode|.
   bool IsContinuousInState(const VCMFrameBuffer& frame,
-                           const VCMDecodingState& decoding_state) const
+                           const VCMDecodingState& decoding_state,
+                           bool ignore_error_mode) const
       EXCLUSIVE_LOCKS_REQUIRED(crit_sect_);
   // Returns true if |frame| is continuous in the |last_decoded_state_|, taking
-  // all decodable frames into account.
-  bool IsContinuous(const VCMFrameBuffer& frame) const
+  // all decodable frames into account and optionally ignoring the
+  // |decode_error_mode|.
+  bool IsContinuous(const VCMFrameBuffer& frame, bool ignore_error_mode) const
       EXCLUSIVE_LOCKS_REQUIRED(crit_sect_);
   // Looks for frames in |incomplete_frames_| which are continuous in the
   // provided |decoded_state|. Starts the search from the timestamp of
@@ -225,6 +227,11 @@ class VCMJitterBuffer {
   // the search from |new_frame|.
   void FindAndInsertContinuousFrames(const VCMFrameBuffer& new_frame)
       EXCLUSIVE_LOCKS_REQUIRED(crit_sect_);
+  // Returns true if no continuous decodable frame has been received for too
+  // long and NACKs are disabled, so a keyframe should be requested from the
+  // sender. Ensures that keyframes are not requested too often.
+  bool TooManyDiscontinuousFrames(int64_t now_ms)
+      EXCLUSIVE_LOCKS_REQUIRED(crit_sect_);
   VCMFrameBuffer* NextFrame() const EXCLUSIVE_LOCKS_REQUIRED(crit_sect_);
   // Returns true if the NACK list was updated to cover sequence numbers up to
   // |sequence_number|. If false a key frame is needed to get into a state where
@@ -332,6 +339,8 @@ class VCMJitterBuffer {
   int num_duplicated_packets_ GUARDED_BY(crit_sect_);
   // Number of packets discarded by the jitter buffer.
   int num_discarded_packets_ GUARDED_BY(crit_sect_);
+  // Time when last decodable frame was received.
+  int64_t time_last_decodable_frame_ GUARDED_BY(crit_sect_);
   // Time when first packet is received.
   int64_t time_first_packet_ms_ GUARDED_BY(crit_sect_);