Wait for keyframe after decoding error.

Bug: chromium:936715
Change-Id: I0a51c8fa0025cb0f8e9afcbe8d8e4a84c2709ecf
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/134960
Commit-Queue: Philip Eliasson <philipel@webrtc.org>
Reviewed-by: Ilya Nikolaevskiy <ilnik@webrtc.org>
Reviewed-by: Rasmus Brandt <brandtr@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#27827}

modules/video_coding/frame_buffer2.h

@@ -65,7 +65,7 @@ class FrameBuffer {
   //  - If the FrameBuffer is stopped then it will return kStopped.
   ReturnReason NextFrame(int64_t max_wait_time_ms,
                          std::unique_ptr<EncodedFrame>* frame_out,
-                         bool keyframe_required = false);
+                         bool keyframe_required);
   void NextFrame(
       int64_t max_wait_time_ms,
       bool keyframe_required,