Add DecodedImageCallback::Decoded() function with custom decode time value.

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

Index: webrtc/modules/video_coding/main/source/timing.h
diff --git a/webrtc/modules/video_coding/main/source/timing.h b/webrtc/modules/video_coding/main/source/timing.h
index d3b8fa673f0e030315d313bb6eabce5347de944b..41dec8ce7f5829644935de74799f942cdaf7d7f2 100644
--- a/webrtc/modules/video_coding/main/source/timing.h
+++ b/webrtc/modules/video_coding/main/source/timing.h
@@ -58,7 +58,7 @@ class VCMTiming {
   // Stops the decoder timer, should be called when the decoder returns a frame
   // or when the decoded frame callback is called.
   int32_t StopDecodeTimer(uint32_t time_stamp,
-                          int64_t start_time_ms,
+                          int32_t decode_time_ms,
                           int64_t now_ms,
                           int64_t render_time_ms);