Revert of MSE: Relax the 'media segment must begin with keyframe' requirement

media/filters/media_source_state.h

Index: media/filters/media_source_state.h
diff --git a/media/filters/media_source_state.h b/media/filters/media_source_state.h
index 1a8e42adb409f36dc86095b39794d4c96a730ded..8d41b1ee0f1a52bbde87ec23987440ca6f893eb5 100644
--- a/media/filters/media_source_state.h
+++ b/media/filters/media_source_state.h
@@ -171,6 +171,16 @@
   TimeDelta append_window_start_during_append_;
   TimeDelta append_window_end_during_append_;
 
+  // Set to true if the next buffers appended within the append window
+  // represent the start of a new media segment. This flag being set
+  // triggers a call to |new_segment_cb_| when the new buffers are
+  // appended. The flag is set on actual media segment boundaries and
+  // when the "append window" filtering causes discontinuities in the
+  // appended data.
+  // TODO(wolenetz/acolwell): Investigate if we need this, or if coded frame
+  // processing's discontinuity logic is enough. See http://crbug.com/351489.
+  bool new_media_segment_;
+
   // Keeps track of whether a media segment is being parsed.
   bool parsing_media_segment_;