Fix multiple Initialize() calls and reenable VEA usage in MediaRecorder for Win8

content/renderer/media_recorder/video_track_recorder.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 "content/renderer/media_recorder/video_track_recorder.h"
 
 #include <utility>
 
 #include "base/bind.h"
 #include "base/logging.h"
 #include "base/macros.h"
 #include "base/memory/ptr_util.h"
 #include "base/sys_info.h"
 #include "base/task_runner_util.h"
 #include "base/threading/thread.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "base/time/time.h"
 #include "base/trace_event/trace_event.h"
 #include "cc/paint/paint_canvas.h"
 #include "cc/paint/paint_surface.h"
+#include "content/child/child_process.h"
 #include "content/renderer/media/renderer_gpu_video_accelerator_factories.h"
 #include "content/renderer/render_thread_impl.h"
 #include "media/base/bind_to_current_loop.h"
 #include "media/base/video_frame.h"
 #include "media/base/video_util.h"
 #include "media/filters/context_3d.h"
 #include "media/renderers/skcanvas_video_renderer.h"
 #include "services/ui/public/cpp/gpu/context_provider_command_buffer.h"
 #include "skia/ext/platform_canvas.h"
 #include "third_party/libyuv/include/libyuv.h"
 #include "ui/gfx/geometry/size.h"
 
-#if defined(OS_WIN)
-#include "base/win/windows_version.h"
-#endif
-
 #if BUILDFLAG(RTC_USE_H264)
 #include "third_party/openh264/src/codec/api/svc/codec_api.h"
 #include "third_party/openh264/src/codec/api/svc/codec_app_def.h"
 #include "third_party/openh264/src/codec/api/svc/codec_def.h"
 #endif  // #if BUILDFLAG(RTC_USE_H264)
 
 extern "C" {
 // VPX_CODEC_DISABLE_COMPAT excludes parts of the libvpx API that provide
 // backwards compatibility for legacy applications using the library.
 #define VPX_CODEC_DISABLE_COMPAT 1
@@ skipping 67 matching lines @@
 #if defined(OS_CHROMEOS)
   // See https://crbug.com/616659.
   return;
 #endif
 
 #if defined(OS_ANDROID)
   // See https://crbug.com/653864.
   return;
 #endif
 
-#if defined(OS_WIN)
-  // See https://crbug.com/698441.
-  if (base::win::GetVersion() < base::win::VERSION_WIN10)
-    return;
-#endif
-
   content::RenderThreadImpl* const render_thread_impl =
       content::RenderThreadImpl::current();
   if (!render_thread_impl) {
     DVLOG(2) << "Couldn't access the render thread";
     return;
   }
 
   media::GpuVideoAcceleratorFactories* const gpu_factories =
       render_thread_impl->GetGpuFactories();
   if (!gpu_factories || !gpu_factories->IsGpuVideoAcceleratorEnabled()) {
@@ skipping 1156 matching lines @@
 
 void VideoTrackRecorder::InitializeEncoder(
     CodecId codec,
     const OnEncodedVideoCB& on_encoded_video_callback,
     int32_t bits_per_second,
     const scoped_refptr<media::VideoFrame>& frame,
     base::TimeTicks capture_time) {
   DVLOG(3) << __func__ << frame->visible_rect().size().ToString();
   DCHECK(main_render_thread_checker_.CalledOnValidThread());
 
+  if (encoder_) {
+    auto* const child_process = ChildProcess::current();
+    if (child_process) {
+      child_process->io_task_runner()->PostTask(
+          FROM_HERE, base::Bind(&VideoTrackRecorder::Encoder::StartFrameEncode,
+                                encoder_, frame, capture_time));
+    }
+    return;
+  }

[mcasas, 2017/03/23 21:14:08]

I'd do:

  // Avoid reinitializing |encoder_|, https://crbug.com/698441.
  DCHECK(RenderThread::Get());
  if (encoder_ && RenderThread::Get()->GetIOTaskRunner()) {
    RenderThread::Get()->GetIOTaskRunner()->PostTask(
        FROM_HERE, base::Bind(&VideoTrackRecorder::Encoder::StartFrameEncode,
                              encoder_, frame, capture_time));
    return;
  }

If DCHECK() doesn't verify in unit tests, add a 
MockRenderThread [1], wdyt?  RenderThread 
conveys clearlier what you want to do than 
ChildProcess IMHO.

[1]
https://cs.chromium.org/chromium/src/content/public/test/mock_render_thread.h...

[emircan, 2017/03/24 18:14:11]

Done. RenderThreadImpl directly calls ChildProcess::io_task_runner() so I wanted
to skip the middle step, see
https://cs.chromium.org/chromium/src/content/renderer/render_thread_impl.cc?r....


Also, we should still return if |!RenderThread::Get()->GetIOTaskRunner()| so I
nested the loop.

+
   MediaStreamVideoSink::DisconnectFromTrack();
 
   const gfx::Size& input_size = frame->visible_rect().size();
   const auto& vea_supported_profile =
       GetCodecEnumerator()->CodecIdToVEAProfile(codec);
   if (vea_supported_profile != media::VIDEO_CODEC_PROFILE_UNKNOWN &&
       input_size.width() >= kVEAEncoderMinResolutionWidth &&
       input_size.height() >= kVEAEncoderMinResolutionHeight) {
     encoder_ = new VEAEncoder(on_encoded_video_callback, bits_per_second,
                               vea_supported_profile, input_size);
@@ skipping 24 matching lines @@
       base::Bind(&VideoTrackRecorder::Encoder::StartFrameEncode, encoder_),
       false);
 }
 
 bool VideoTrackRecorder::CanEncodeAlphaChannelForTesting() {
   DCHECK(encoder_);
   return encoder_->CanEncodeAlphaChannel();
 }
 
 }  // namespace content