Don't reset the codec state for a flush; this kills the frames.

media/gpu/avda_codec_image.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "media/gpu/avda_codec_image.h"
 
 #include <string.h>
 
 #include <memory>
 
@@ skipping 17 matching lines @@
     : shared_state_(shared_state),
       codec_buffer_index_(kInvalidCodecBufferIndex),
       media_codec_(codec),
       decoder_(decoder),
       surface_texture_(surface_texture),
       texture_(0),
       picture_buffer_id_(picture_buffer_id) {
   // Default to a sane guess of "flip Y", just in case we can't get
   // the matrix on the first call.
   memset(gl_matrix_, 0, sizeof(gl_matrix_));
-  gl_matrix_[0] = gl_matrix_[10] = gl_matrix_[15] = 1.0f;
+  gl_matrix_[0] = gl_matrix_[10] = gl_matrix_[13] = gl_matrix_[15] = 1.0f;
   gl_matrix_[5] = -1.0f;
   shared_state_->SetImageForPicture(picture_buffer_id_, this);
 }
 
 AVDACodecImage::~AVDACodecImage() {
   shared_state_->SetImageForPicture(picture_buffer_id_, nullptr);
 }
 
 void AVDACodecImage::Destroy(bool have_context) {}
 
@@ skipping 228 matching lines @@
 }
 
 bool AVDACodecImage::IsCodecBufferOutstanding() const {
   static_assert(kUpdateOnly < 0 && kUpdateOnly > kRendered &&
                     kRendered > kInvalidCodecBufferIndex,
                 "Codec buffer index enum values are not ordered correctly.");
   return codec_buffer_index_ > kRendered && media_codec_;
 }
 
 }  // namespace media