V4L2VEA: Improve H264 stream header handling.

media/gpu/video_encode_accelerator_unittest.cc

Index: media/gpu/video_encode_accelerator_unittest.cc
diff --git a/media/gpu/video_encode_accelerator_unittest.cc b/media/gpu/video_encode_accelerator_unittest.cc
index f64d4e42ed612bd9966526a245ffbe47034b3d30..f2050d358a8ad9f2c19d510d017226cdfd420a70 100644
--- a/media/gpu/video_encode_accelerator_unittest.cc
+++ b/media/gpu/video_encode_accelerator_unittest.cc
@@ -591,6 +591,7 @@ void H264Validator::ProcessStreamBuffer(const uint8_t* stream, size_t size) {
       // fallthrough
       case H264NALU::kNonIDRSlice: {
         ASSERT_TRUE(seen_idr_);
+        seen_sps_ = seen_pps_ = false;
         if (!frame_cb_.Run(keyframe))
           return;
         break;