Forcibly disable MacVDA, even for users who ignore the GPU blacklist.

content/common/gpu/media/mac_video_decode_accelerator.mm

 // Copyright (c) 2012 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 "content/common/gpu/media/mac_video_decode_accelerator.h"
 
 #include "base/bind.h"
 #include "base/file_path.h"
 #import "base/mac/foundation_util.h"
 #import "base/memory/ref_counted_memory.h"
@@ skipping 86 matching lines @@
 MacVideoDecodeAccelerator::MacVideoDecodeAccelerator(
     CGLContextObj cgl_context, media::VideoDecodeAccelerator::Client* client)
     : client_(client),
       cgl_context_(cgl_context),
       did_build_config_record_(false) {
 }
 
 bool MacVideoDecodeAccelerator::Initialize(media::VideoCodecProfile profile) {
   DCHECK(CalledOnValidThread());
 
+  // MacVDA still fails on too many videos to be useful, even to users who
+  // ignore the GPU blacklist.  Fail unconditionally here until enough of
+  // crbug.com/133828's blockers are resolved.
+  if (true)
+    return false;
+
   if (profile < media::H264PROFILE_MIN || profile > media::H264PROFILE_MAX)
     return false;
 
   IOSurfaceSupport* io_surface_support = IOSurfaceSupport::Initialize();
   if (!io_surface_support)
     return false;
 
   MessageLoop::current()->PostTask(FROM_HERE, base::Bind(
       &MacVideoDecodeAccelerator::NotifyInitializeDone, base::AsWeakPtr(this)));
   return true;
@@ skipping 258 matching lines @@
 MacVideoDecodeAccelerator::UsedPictureInfo::~UsedPictureInfo() {
 }
 
 MacVideoDecodeAccelerator::DecodedImageInfo::DecodedImageInfo() {
 }
 
 MacVideoDecodeAccelerator::DecodedImageInfo::~DecodedImageInfo() {
 }
 
 }  // namespace content