Migrate content/common/gpu/media code to media/gpu

content/common/gpu/media/v4l2_video_decode_accelerator.cc

-// Copyright 2014 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 <dlfcn.h>
-#include <errno.h>
-#include <fcntl.h>
-#include <linux/videodev2.h>
-#include <poll.h>
-#include <string.h>
-#include <sys/eventfd.h>
-#include <sys/ioctl.h>
-#include <sys/mman.h>
-
-#include "base/bind.h"
-#include "base/command_line.h"
-#include "base/macros.h"
-#include "base/message_loop/message_loop.h"
-#include "base/numerics/safe_conversions.h"
-#include "base/thread_task_runner_handle.h"
-#include "base/trace_event/trace_event.h"
-#include "build/build_config.h"
-#include "content/common/gpu/media/shared_memory_region.h"
-#include "content/common/gpu/media/v4l2_video_decode_accelerator.h"
-#include "media/base/media_switches.h"
-#include "media/filters/h264_parser.h"
-#include "ui/gfx/geometry/rect.h"
-#include "ui/gl/gl_context.h"
-#include "ui/gl/scoped_binders.h"
-
-#define NOTIFY_ERROR(x)                        \
-  do {                                         \
-    LOG(ERROR) << "Setting error state:" << x; \
-    SetErrorState(x);                          \
-  } while (0)
-
-#define IOCTL_OR_ERROR_RETURN_VALUE(type, arg, value, type_str)        \
-  do {                                                                 \
-    if (device_->Ioctl(type, arg) != 0) {                              \
-      PLOG(ERROR) << __func__ << "(): ioctl() failed: " << type_str;   \
-      NOTIFY_ERROR(PLATFORM_FAILURE);                                  \
-      return value;                                                    \
-    }                                                                  \
-  } while (0)
-
-#define IOCTL_OR_ERROR_RETURN(type, arg) \
-  IOCTL_OR_ERROR_RETURN_VALUE(type, arg, ((void)0), #type)
-
-#define IOCTL_OR_ERROR_RETURN_FALSE(type, arg) \
-  IOCTL_OR_ERROR_RETURN_VALUE(type, arg, false, #type)
-
-#define IOCTL_OR_LOG_ERROR(type, arg)                              \
-  do {                                                             \
-    if (device_->Ioctl(type, arg) != 0)                            \
-      PLOG(ERROR) << __func__ << "(): ioctl() failed: " << #type;  \
-  } while (0)
-
-namespace content {
-
-// static
-const uint32_t V4L2VideoDecodeAccelerator::supported_input_fourccs_[] = {
-    V4L2_PIX_FMT_H264, V4L2_PIX_FMT_VP8, V4L2_PIX_FMT_VP9,
-};
-
-struct V4L2VideoDecodeAccelerator::BitstreamBufferRef {
-  BitstreamBufferRef(
-      base::WeakPtr<Client>& client,
-      scoped_refptr<base::SingleThreadTaskRunner>& client_task_runner,
-      std::unique_ptr<SharedMemoryRegion> shm,
-      int32_t input_id);
-  ~BitstreamBufferRef();
-  const base::WeakPtr<Client> client;
-  const scoped_refptr<base::SingleThreadTaskRunner> client_task_runner;
-  const std::unique_ptr<SharedMemoryRegion> shm;
-  size_t bytes_used;
-  const int32_t input_id;
-};
-
-struct V4L2VideoDecodeAccelerator::EGLSyncKHRRef {
-  EGLSyncKHRRef(EGLDisplay egl_display, EGLSyncKHR egl_sync);
-  ~EGLSyncKHRRef();
-  EGLDisplay const egl_display;
-  EGLSyncKHR egl_sync;
-};
-
-struct V4L2VideoDecodeAccelerator::PictureRecord {
-  PictureRecord(bool cleared, const media::Picture& picture);
-  ~PictureRecord();
-  bool cleared;  // Whether the texture is cleared and safe to render from.
-  media::Picture picture;  // The decoded picture.
-};
-
-V4L2VideoDecodeAccelerator::BitstreamBufferRef::BitstreamBufferRef(
-    base::WeakPtr<Client>& client,
-    scoped_refptr<base::SingleThreadTaskRunner>& client_task_runner,
-    std::unique_ptr<SharedMemoryRegion> shm,
-    int32_t input_id)
-    : client(client),
-      client_task_runner(client_task_runner),
-      shm(std::move(shm)),
-      bytes_used(0),
-      input_id(input_id) {}
-
-V4L2VideoDecodeAccelerator::BitstreamBufferRef::~BitstreamBufferRef() {
-  if (input_id >= 0) {
-    client_task_runner->PostTask(
-        FROM_HERE,
-        base::Bind(&Client::NotifyEndOfBitstreamBuffer, client, input_id));
-  }
-}
-
-V4L2VideoDecodeAccelerator::EGLSyncKHRRef::EGLSyncKHRRef(
-    EGLDisplay egl_display, EGLSyncKHR egl_sync)
-    : egl_display(egl_display),
-      egl_sync(egl_sync) {
-}
-
-V4L2VideoDecodeAccelerator::EGLSyncKHRRef::~EGLSyncKHRRef() {
-  // We don't check for eglDestroySyncKHR failures, because if we get here
-  // with a valid sync object, something went wrong and we are getting
-  // destroyed anyway.
-  if (egl_sync != EGL_NO_SYNC_KHR)
-    eglDestroySyncKHR(egl_display, egl_sync);
-}
-
-V4L2VideoDecodeAccelerator::InputRecord::InputRecord()
-    : at_device(false),
-      address(NULL),
-      length(0),
-      bytes_used(0),
-      input_id(-1) {
-}
-
-V4L2VideoDecodeAccelerator::InputRecord::~InputRecord() {
-}
-
-V4L2VideoDecodeAccelerator::OutputRecord::OutputRecord()
-    : at_device(false),
-      at_client(false),
-      egl_image(EGL_NO_IMAGE_KHR),
-      egl_sync(EGL_NO_SYNC_KHR),
-      picture_id(-1),
-      cleared(false) {
-}
-
-V4L2VideoDecodeAccelerator::OutputRecord::~OutputRecord() {}
-
-V4L2VideoDecodeAccelerator::PictureRecord::PictureRecord(
-    bool cleared,
-    const media::Picture& picture)
-    : cleared(cleared), picture(picture) {}
-
-V4L2VideoDecodeAccelerator::PictureRecord::~PictureRecord() {}
-
-V4L2VideoDecodeAccelerator::V4L2VideoDecodeAccelerator(
-    EGLDisplay egl_display,
-    const GetGLContextCallback& get_gl_context_cb,
-    const MakeGLContextCurrentCallback& make_context_current_cb,
-    const scoped_refptr<V4L2Device>& device)
-    : child_task_runner_(base::ThreadTaskRunnerHandle::Get()),
-      decoder_thread_("V4L2DecoderThread"),
-      decoder_state_(kUninitialized),
-      device_(device),
-      decoder_delay_bitstream_buffer_id_(-1),
-      decoder_current_input_buffer_(-1),
-      decoder_decode_buffer_tasks_scheduled_(0),
-      decoder_frames_at_client_(0),
-      decoder_flushing_(false),
-      resolution_change_reset_pending_(false),
-      decoder_partial_frame_pending_(false),
-      input_streamon_(false),
-      input_buffer_queued_count_(0),
-      output_streamon_(false),
-      output_buffer_queued_count_(0),
-      output_dpb_size_(0),
-      output_planes_count_(0),
-      picture_clearing_count_(0),
-      pictures_assigned_(false, false),
-      device_poll_thread_("V4L2DevicePollThread"),
-      egl_display_(egl_display),
-      get_gl_context_cb_(get_gl_context_cb),
-      make_context_current_cb_(make_context_current_cb),
-      video_profile_(media::VIDEO_CODEC_PROFILE_UNKNOWN),
-      output_format_fourcc_(0),
-      weak_this_factory_(this) {
-  weak_this_ = weak_this_factory_.GetWeakPtr();
-}
-
-V4L2VideoDecodeAccelerator::~V4L2VideoDecodeAccelerator() {
-  DCHECK(!decoder_thread_.IsRunning());
-  DCHECK(!device_poll_thread_.IsRunning());
-
-  DestroyInputBuffers();
-  DestroyOutputBuffers();
-
-  // These maps have members that should be manually destroyed, e.g. file
-  // descriptors, mmap() segments, etc.
-  DCHECK(input_buffer_map_.empty());
-  DCHECK(output_buffer_map_.empty());
-}
-
-bool V4L2VideoDecodeAccelerator::Initialize(const Config& config,
-                                            Client* client) {
-  DVLOG(3) << "Initialize()";
-  DCHECK(child_task_runner_->BelongsToCurrentThread());
-  DCHECK_EQ(decoder_state_, kUninitialized);
-
-  if (get_gl_context_cb_.is_null() || make_context_current_cb_.is_null()) {
-    NOTREACHED() << "GL callbacks are required for this VDA";
-    return false;
-  }
-
-  if (config.is_encrypted) {
-    NOTREACHED() << "Encrypted streams are not supported for this VDA";
-    return false;
-  }
-
-  if (!device_->SupportsDecodeProfileForV4L2PixelFormats(
-          config.profile, arraysize(supported_input_fourccs_),
-          supported_input_fourccs_)) {
-    DVLOG(1) << "Initialize(): unsupported profile=" << config.profile;
-    return false;
-  }
-
-  client_ptr_factory_.reset(new base::WeakPtrFactory<Client>(client));
-  client_ = client_ptr_factory_->GetWeakPtr();
-  // If we haven't been set up to decode on separate thread via
-  // TryToSetupDecodeOnSeparateThread(), use the main thread/client for
-  // decode tasks.
-  if (!decode_task_runner_) {
-    decode_task_runner_ = child_task_runner_;
-    DCHECK(!decode_client_);
-    decode_client_ = client_;
-  }
-
-  video_profile_ = config.profile;
-
-  if (egl_display_ == EGL_NO_DISPLAY) {
-    LOG(ERROR) << "Initialize(): could not get EGLDisplay";
-    return false;
-  }
-
-  // We need the context to be initialized to query extensions.
-  if (!make_context_current_cb_.Run()) {
-    LOG(ERROR) << "Initialize(): could not make context current";
-    return false;
-  }
-
-// TODO(posciak): crbug.com/450898.
-#if defined(ARCH_CPU_ARMEL)
-  if (!gfx::g_driver_egl.ext.b_EGL_KHR_fence_sync) {
-    LOG(ERROR) << "Initialize(): context does not have EGL_KHR_fence_sync";
-    return false;
-  }
-#endif
-
-  // Capabilities check.
-  struct v4l2_capability caps;
-  const __u32 kCapsRequired = V4L2_CAP_VIDEO_M2M_MPLANE | V4L2_CAP_STREAMING;
-  IOCTL_OR_ERROR_RETURN_FALSE(VIDIOC_QUERYCAP, &caps);
-  if ((caps.capabilities & kCapsRequired) != kCapsRequired) {
-    LOG(ERROR) << "Initialize(): ioctl() failed: VIDIOC_QUERYCAP"
-        ", caps check failed: 0x" << std::hex << caps.capabilities;
-    return false;
-  }
-
-  if (!SetupFormats())
-    return false;
-
-  // Subscribe to the resolution change event.
-  struct v4l2_event_subscription sub;
-  memset(&sub, 0, sizeof(sub));
-  sub.type = V4L2_EVENT_SOURCE_CHANGE;
-  IOCTL_OR_ERROR_RETURN_FALSE(VIDIOC_SUBSCRIBE_EVENT, &sub);
-
-  if (video_profile_ >= media::H264PROFILE_MIN &&
-      video_profile_ <= media::H264PROFILE_MAX) {
-    decoder_h264_parser_.reset(new media::H264Parser());
-  }
-
-  if (!CreateInputBuffers())
-    return false;
-
-  if (!decoder_thread_.Start()) {
-    LOG(ERROR) << "Initialize(): decoder thread failed to start";
-    return false;
-  }
-
-  decoder_state_ = kInitialized;
-
-  // StartDevicePoll will NOTIFY_ERROR on failure, so IgnoreResult is fine here.
-  decoder_thread_.message_loop()->PostTask(
-      FROM_HERE,
-      base::Bind(
-          base::IgnoreResult(&V4L2VideoDecodeAccelerator::StartDevicePoll),
-          base::Unretained(this)));
-
-  return true;
-}
-
-void V4L2VideoDecodeAccelerator::Decode(
-    const media::BitstreamBuffer& bitstream_buffer) {
-  DVLOG(1) << "Decode(): input_id=" << bitstream_buffer.id()
-           << ", size=" << bitstream_buffer.size();
-  DCHECK(decode_task_runner_->BelongsToCurrentThread());
-
-  if (bitstream_buffer.id() < 0) {
-    LOG(ERROR) << "Invalid bitstream_buffer, id: " << bitstream_buffer.id();
-    if (base::SharedMemory::IsHandleValid(bitstream_buffer.handle()))
-      base::SharedMemory::CloseHandle(bitstream_buffer.handle());
-    NOTIFY_ERROR(INVALID_ARGUMENT);
-    return;
-  }
-
-  // DecodeTask() will take care of running a DecodeBufferTask().
-  decoder_thread_.message_loop()->PostTask(FROM_HERE, base::Bind(
-      &V4L2VideoDecodeAccelerator::DecodeTask, base::Unretained(this),
-      bitstream_buffer));
-}
-
-void V4L2VideoDecodeAccelerator::AssignPictureBuffers(
-    const std::vector<media::PictureBuffer>& buffers) {
-  DVLOG(3) << "AssignPictureBuffers(): buffer_count=" << buffers.size();
-  DCHECK(child_task_runner_->BelongsToCurrentThread());
-
-  const uint32_t req_buffer_count =
-      output_dpb_size_ + kDpbOutputBufferExtraCount;
-
-  if (buffers.size() < req_buffer_count) {
-    LOG(ERROR) << "AssignPictureBuffers(): Failed to provide requested picture"
-                  " buffers. (Got " << buffers.size()
-               << ", requested " << req_buffer_count << ")";
-    NOTIFY_ERROR(INVALID_ARGUMENT);
-    return;
-  }
-
-  gfx::GLContext* gl_context = get_gl_context_cb_.Run();
-  if (!gl_context || !make_context_current_cb_.Run()) {
-    LOG(ERROR) << "AssignPictureBuffers(): could not make context current";
-    NOTIFY_ERROR(PLATFORM_FAILURE);
-    return;
-  }
-
-  gfx::ScopedTextureBinder bind_restore(GL_TEXTURE_EXTERNAL_OES, 0);
-
-  // It's safe to manipulate all the buffer state here, because the decoder
-  // thread is waiting on pictures_assigned_.
-
-  // Allocate the output buffers.
-  struct v4l2_requestbuffers reqbufs;
-  memset(&reqbufs, 0, sizeof(reqbufs));
-  reqbufs.count  = buffers.size();
-  reqbufs.type   = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
-  reqbufs.memory = V4L2_MEMORY_MMAP;
-  IOCTL_OR_ERROR_RETURN(VIDIOC_REQBUFS, &reqbufs);
-
-  if (reqbufs.count != buffers.size()) {
-    DLOG(ERROR) << "Could not allocate enough output buffers";
-    NOTIFY_ERROR(PLATFORM_FAILURE);
-    return;
-  }
-
-  output_buffer_map_.resize(buffers.size());
-
-  DCHECK(free_output_buffers_.empty());
-  for (size_t i = 0; i < output_buffer_map_.size(); ++i) {
-    DCHECK(buffers[i].size() == coded_size_);
-
-    OutputRecord& output_record = output_buffer_map_[i];
-    DCHECK(!output_record.at_device);
-    DCHECK(!output_record.at_client);
-    DCHECK_EQ(output_record.egl_image, EGL_NO_IMAGE_KHR);
-    DCHECK_EQ(output_record.egl_sync, EGL_NO_SYNC_KHR);
-    DCHECK_EQ(output_record.picture_id, -1);
-    DCHECK_EQ(output_record.cleared, false);
-    DCHECK_LE(1u, buffers[i].texture_ids().size());
-
-    EGLImageKHR egl_image = device_->CreateEGLImage(
-        egl_display_, gl_context->GetHandle(), buffers[i].texture_ids()[0],
-        coded_size_, i, output_format_fourcc_, output_planes_count_);
-    if (egl_image == EGL_NO_IMAGE_KHR) {
-      LOG(ERROR) << "AssignPictureBuffers(): could not create EGLImageKHR";
-      // Ownership of EGLImages allocated in previous iterations of this loop
-      // has been transferred to output_buffer_map_. After we error-out here
-      // the destructor will handle their cleanup.
-      NOTIFY_ERROR(PLATFORM_FAILURE);
-      return;
-    }
-
-    output_record.egl_image = egl_image;
-    output_record.picture_id = buffers[i].id();
-    free_output_buffers_.push(i);
-    DVLOG(3) << "AssignPictureBuffers(): buffer[" << i
-             << "]: picture_id=" << output_record.picture_id;
-  }
-
-  pictures_assigned_.Signal();
-}
-
-void V4L2VideoDecodeAccelerator::ReusePictureBuffer(int32_t picture_buffer_id) {
-  DVLOG(3) << "ReusePictureBuffer(): picture_buffer_id=" << picture_buffer_id;
-  // Must be run on child thread, as we'll insert a sync in the EGL context.
-  DCHECK(child_task_runner_->BelongsToCurrentThread());
-
-  if (!make_context_current_cb_.Run()) {
-    LOG(ERROR) << "ReusePictureBuffer(): could not make context current";
-    NOTIFY_ERROR(PLATFORM_FAILURE);
-    return;
-  }
-
-  EGLSyncKHR egl_sync = EGL_NO_SYNC_KHR;
-// TODO(posciak): crbug.com/450898.
-#if defined(ARCH_CPU_ARMEL)
-  egl_sync = eglCreateSyncKHR(egl_display_, EGL_SYNC_FENCE_KHR, NULL);
-  if (egl_sync == EGL_NO_SYNC_KHR) {
-    LOG(ERROR) << "ReusePictureBuffer(): eglCreateSyncKHR() failed";
-    NOTIFY_ERROR(PLATFORM_FAILURE);
-    return;
-  }
-#endif
-
-  std::unique_ptr<EGLSyncKHRRef> egl_sync_ref(
-      new EGLSyncKHRRef(egl_display_, egl_sync));
-  decoder_thread_.message_loop()->PostTask(FROM_HERE, base::Bind(
-      &V4L2VideoDecodeAccelerator::ReusePictureBufferTask,
-      base::Unretained(this), picture_buffer_id, base::Passed(&egl_sync_ref)));
-}
-
-void V4L2VideoDecodeAccelerator::Flush() {
-  DVLOG(3) << "Flush()";
-  DCHECK(child_task_runner_->BelongsToCurrentThread());
-  decoder_thread_.message_loop()->PostTask(FROM_HERE, base::Bind(
-      &V4L2VideoDecodeAccelerator::FlushTask, base::Unretained(this)));
-}
-
-void V4L2VideoDecodeAccelerator::Reset() {
-  DVLOG(3) << "Reset()";
-  DCHECK(child_task_runner_->BelongsToCurrentThread());
-  decoder_thread_.message_loop()->PostTask(FROM_HERE, base::Bind(
-      &V4L2VideoDecodeAccelerator::ResetTask, base::Unretained(this)));
-}
-
-void V4L2VideoDecodeAccelerator::Destroy() {
-  DVLOG(3) << "Destroy()";
-  DCHECK(child_task_runner_->BelongsToCurrentThread());
-
-  // We're destroying; cancel all callbacks.
-  client_ptr_factory_.reset();
-  weak_this_factory_.InvalidateWeakPtrs();
-
-  // If the decoder thread is running, destroy using posted task.
-  if (decoder_thread_.IsRunning()) {
-    decoder_thread_.message_loop()->PostTask(FROM_HERE, base::Bind(
-        &V4L2VideoDecodeAccelerator::DestroyTask, base::Unretained(this)));
-    pictures_assigned_.Signal();
-    // DestroyTask() will cause the decoder_thread_ to flush all tasks.
-    decoder_thread_.Stop();
-  } else {
-    // Otherwise, call the destroy task directly.
-    DestroyTask();
-  }
-
-  delete this;
-}
-
-bool V4L2VideoDecodeAccelerator::TryToSetupDecodeOnSeparateThread(
-    const base::WeakPtr<Client>& decode_client,
-    const scoped_refptr<base::SingleThreadTaskRunner>& decode_task_runner) {
-  decode_client_ = decode_client_;
-  decode_task_runner_ = decode_task_runner;
-  return true;
-}
-
-// static
-media::VideoDecodeAccelerator::SupportedProfiles
-V4L2VideoDecodeAccelerator::GetSupportedProfiles() {
-  scoped_refptr<V4L2Device> device = V4L2Device::Create(V4L2Device::kDecoder);
-  if (!device)
-    return SupportedProfiles();
-
-  return device->GetSupportedDecodeProfiles(arraysize(supported_input_fourccs_),
-                                            supported_input_fourccs_);
-}
-
-void V4L2VideoDecodeAccelerator::DecodeTask(
-    const media::BitstreamBuffer& bitstream_buffer) {
-  DVLOG(3) << "DecodeTask(): input_id=" << bitstream_buffer.id();
-  DCHECK_EQ(decoder_thread_.message_loop(), base::MessageLoop::current());
-  DCHECK_NE(decoder_state_, kUninitialized);
-  TRACE_EVENT1("Video Decoder", "V4L2VDA::DecodeTask", "input_id",
-               bitstream_buffer.id());
-
-  std::unique_ptr<BitstreamBufferRef> bitstream_record(new BitstreamBufferRef(
-      decode_client_, decode_task_runner_,
-      std::unique_ptr<SharedMemoryRegion>(
-          new SharedMemoryRegion(bitstream_buffer, true)),
-      bitstream_buffer.id()));
-  if (!bitstream_record->shm->Map()) {
-    LOG(ERROR) << "Decode(): could not map bitstream_buffer";
-    NOTIFY_ERROR(UNREADABLE_INPUT);
-    return;
-  }
-  DVLOG(3) << "DecodeTask(): mapped at=" << bitstream_record->shm->memory();
-
-  if (decoder_state_ == kResetting || decoder_flushing_) {
-    // In the case that we're resetting or flushing, we need to delay decoding
-    // the BitstreamBuffers that come after the Reset() or Flush() call.  When
-    // we're here, we know that this DecodeTask() was scheduled by a Decode()
-    // call that came after (in the client thread) the Reset() or Flush() call;
-    // thus set up the delay if necessary.
-    if (decoder_delay_bitstream_buffer_id_ == -1)
-      decoder_delay_bitstream_buffer_id_ = bitstream_record->input_id;
-  } else if (decoder_state_ == kError) {
-    DVLOG(2) << "DecodeTask(): early out: kError state";
-    return;
-  }
-
-  decoder_input_queue_.push(
-      linked_ptr<BitstreamBufferRef>(bitstream_record.release()));
-  decoder_decode_buffer_tasks_scheduled_++;
-  DecodeBufferTask();
-}
-
-void V4L2VideoDecodeAccelerator::DecodeBufferTask() {
-  DVLOG(3) << "DecodeBufferTask()";
-  DCHECK_EQ(decoder_thread_.message_loop(), base::MessageLoop::current());
-  DCHECK_NE(decoder_state_, kUninitialized);
-  TRACE_EVENT0("Video Decoder", "V4L2VDA::DecodeBufferTask");
-
-  decoder_decode_buffer_tasks_scheduled_--;
-
-  if (decoder_state_ == kResetting) {
-    DVLOG(2) << "DecodeBufferTask(): early out: kResetting state";
-    return;
-  } else if (decoder_state_ == kError) {
-    DVLOG(2) << "DecodeBufferTask(): early out: kError state";
-    return;
-  } else if (decoder_state_ == kChangingResolution) {
-    DVLOG(2) << "DecodeBufferTask(): early out: resolution change pending";
-    return;
-  }
-
-  if (decoder_current_bitstream_buffer_ == NULL) {
-    if (decoder_input_queue_.empty()) {
-      // We're waiting for a new buffer -- exit without scheduling a new task.
-      return;
-    }
-    linked_ptr<BitstreamBufferRef>& buffer_ref = decoder_input_queue_.front();
-    if (decoder_delay_bitstream_buffer_id_ == buffer_ref->input_id) {
-      // We're asked to delay decoding on this and subsequent buffers.
-      return;
-    }
-
-    // Setup to use the next buffer.
-    decoder_current_bitstream_buffer_.reset(buffer_ref.release());
-    decoder_input_queue_.pop();
-    const auto& shm = decoder_current_bitstream_buffer_->shm;
-    if (shm) {
-      DVLOG(3) << "DecodeBufferTask(): reading input_id="
-               << decoder_current_bitstream_buffer_->input_id
-               << ", addr=" << shm->memory() << ", size=" << shm->size();
-    } else {
-      DCHECK_EQ(decoder_current_bitstream_buffer_->input_id, kFlushBufferId);
-      DVLOG(3) << "DecodeBufferTask(): reading input_id=kFlushBufferId";
-    }
-  }
-  bool schedule_task = false;
-  size_t decoded_size = 0;
-  const auto& shm = decoder_current_bitstream_buffer_->shm;
-  if (!shm) {
-    // This is a dummy buffer, queued to flush the pipe.  Flush.
-    DCHECK_EQ(decoder_current_bitstream_buffer_->input_id, kFlushBufferId);
-    // Enqueue a buffer guaranteed to be empty.  To do that, we flush the
-    // current input, enqueue no data to the next frame, then flush that down.
-    schedule_task = true;
-    if (decoder_current_input_buffer_ != -1 &&
-        input_buffer_map_[decoder_current_input_buffer_].input_id !=
-            kFlushBufferId)
-      schedule_task = FlushInputFrame();
-
-    if (schedule_task && AppendToInputFrame(NULL, 0) && FlushInputFrame()) {
-      DVLOG(2) << "DecodeBufferTask(): enqueued flush buffer";
-      decoder_partial_frame_pending_ = false;
-      schedule_task = true;
-    } else {
-      // If we failed to enqueue the empty buffer (due to pipeline
-      // backpressure), don't advance the bitstream buffer queue, and don't
-      // schedule the next task.  This bitstream buffer queue entry will get
-      // reprocessed when the pipeline frees up.
-      schedule_task = false;
-    }
-  } else if (shm->size() == 0) {
-    // This is a buffer queued from the client that has zero size.  Skip.
-    schedule_task = true;
-  } else {
-    // This is a buffer queued from the client, with actual contents.  Decode.
-    const uint8_t* const data =
-        reinterpret_cast<const uint8_t*>(shm->memory()) +
-        decoder_current_bitstream_buffer_->bytes_used;
-    const size_t data_size =
-        shm->size() - decoder_current_bitstream_buffer_->bytes_used;
-    if (!AdvanceFrameFragment(data, data_size, &decoded_size)) {
-      NOTIFY_ERROR(UNREADABLE_INPUT);
-      return;
-    }
-    // AdvanceFrameFragment should not return a size larger than the buffer
-    // size, even on invalid data.
-    CHECK_LE(decoded_size, data_size);
-
-    switch (decoder_state_) {
-      case kInitialized:
-      case kAfterReset:
-        schedule_task = DecodeBufferInitial(data, decoded_size, &decoded_size);
-        break;
-      case kDecoding:
-        schedule_task = DecodeBufferContinue(data, decoded_size);
-        break;
-      default:
-        NOTIFY_ERROR(ILLEGAL_STATE);
-        return;
-    }
-  }
-  if (decoder_state_ == kError) {
-    // Failed during decode.
-    return;
-  }
-
-  if (schedule_task) {
-    decoder_current_bitstream_buffer_->bytes_used += decoded_size;
-    if ((shm ? shm->size() : 0) ==
-        decoder_current_bitstream_buffer_->bytes_used) {
-      // Our current bitstream buffer is done; return it.
-      int32_t input_id = decoder_current_bitstream_buffer_->input_id;
-      DVLOG(3) << "DecodeBufferTask(): finished input_id=" << input_id;
-      // BitstreamBufferRef destructor calls NotifyEndOfBitstreamBuffer().
-      decoder_current_bitstream_buffer_.reset();
-    }
-    ScheduleDecodeBufferTaskIfNeeded();
-  }
-}
-
-bool V4L2VideoDecodeAccelerator::AdvanceFrameFragment(const uint8_t* data,
-                                                      size_t size,
-                                                      size_t* endpos) {
-  if (video_profile_ >= media::H264PROFILE_MIN &&
-      video_profile_ <= media::H264PROFILE_MAX) {
-    // For H264, we need to feed HW one frame at a time.  This is going to take
-    // some parsing of our input stream.
-    decoder_h264_parser_->SetStream(data, size);
-    media::H264NALU nalu;
-    media::H264Parser::Result result;
-    *endpos = 0;
-
-    // Keep on peeking the next NALs while they don't indicate a frame
-    // boundary.
-    for (;;) {
-      bool end_of_frame = false;
-      result = decoder_h264_parser_->AdvanceToNextNALU(&nalu);
-      if (result == media::H264Parser::kInvalidStream ||
-          result == media::H264Parser::kUnsupportedStream)
-        return false;
-      if (result == media::H264Parser::kEOStream) {
-        // We've reached the end of the buffer before finding a frame boundary.
-        decoder_partial_frame_pending_ = true;
-        return true;
-      }
-      switch (nalu.nal_unit_type) {
-        case media::H264NALU::kNonIDRSlice:
-        case media::H264NALU::kIDRSlice:
-          if (nalu.size < 1)
-            return false;
-          // For these two, if the "first_mb_in_slice" field is zero, start a
-          // new frame and return.  This field is Exp-Golomb coded starting on
-          // the eighth data bit of the NAL; a zero value is encoded with a
-          // leading '1' bit in the byte, which we can detect as the byte being
-          // (unsigned) greater than or equal to 0x80.
-          if (nalu.data[1] >= 0x80) {
-            end_of_frame = true;
-            break;
-          }
-          break;
-        case media::H264NALU::kSEIMessage:
-        case media::H264NALU::kSPS:
-        case media::H264NALU::kPPS:
-        case media::H264NALU::kAUD:
-        case media::H264NALU::kEOSeq:
-        case media::H264NALU::kEOStream:
-        case media::H264NALU::kReserved14:
-        case media::H264NALU::kReserved15:
-        case media::H264NALU::kReserved16:
-        case media::H264NALU::kReserved17:
-        case media::H264NALU::kReserved18:
-          // These unconditionally signal a frame boundary.
-          end_of_frame = true;
-          break;
-        default:
-          // For all others, keep going.
-          break;
-      }
-      if (end_of_frame) {
-        if (!decoder_partial_frame_pending_ && *endpos == 0) {
-          // The frame was previously restarted, and we haven't filled the
-          // current frame with any contents yet.  Start the new frame here and
-          // continue parsing NALs.
-        } else {
-          // The frame wasn't previously restarted and/or we have contents for
-          // the current frame; signal the start of a new frame here: we don't
-          // have a partial frame anymore.
-          decoder_partial_frame_pending_ = false;
-          return true;
-        }
-      }
-      *endpos = (nalu.data + nalu.size) - data;
-    }
-    NOTREACHED();
-    return false;
-  } else {
-    DCHECK_GE(video_profile_, media::VP8PROFILE_MIN);
-    DCHECK_LE(video_profile_, media::VP9PROFILE_MAX);
-    // For VP8/9, we can just dump the entire buffer.  No fragmentation needed,
-    // and we never return a partial frame.
-    *endpos = size;
-    decoder_partial_frame_pending_ = false;
-    return true;
-  }
-}
-
-void V4L2VideoDecodeAccelerator::ScheduleDecodeBufferTaskIfNeeded() {
-  DCHECK_EQ(decoder_thread_.message_loop(), base::MessageLoop::current());
-
-  // If we're behind on tasks, schedule another one.
-  int buffers_to_decode = decoder_input_queue_.size();
-  if (decoder_current_bitstream_buffer_ != NULL)
-    buffers_to_decode++;
-  if (decoder_decode_buffer_tasks_scheduled_ < buffers_to_decode) {
-    decoder_decode_buffer_tasks_scheduled_++;
-    decoder_thread_.message_loop()->PostTask(FROM_HERE, base::Bind(
-        &V4L2VideoDecodeAccelerator::DecodeBufferTask,
-        base::Unretained(this)));
-  }
-}
-
-bool V4L2VideoDecodeAccelerator::DecodeBufferInitial(
-    const void* data, size_t size, size_t* endpos) {
-  DVLOG(3) << "DecodeBufferInitial(): data=" << data << ", size=" << size;
-  DCHECK_EQ(decoder_thread_.message_loop(), base::MessageLoop::current());
-  DCHECK_NE(decoder_state_, kUninitialized);
-  DCHECK_NE(decoder_state_, kDecoding);
-  // Initial decode.  We haven't been able to get output stream format info yet.
-  // Get it, and start decoding.
-
-  // Copy in and send to HW.
-  if (!AppendToInputFrame(data, size))
-    return false;
-
-  // If we only have a partial frame, don't flush and process yet.
-  if (decoder_partial_frame_pending_)
-    return true;
-
-  if (!FlushInputFrame())
-    return false;
-
-  // Recycle buffers.
-  Dequeue();
-
-  // Check and see if we have format info yet.
-  struct v4l2_format format;
-  gfx::Size visible_size;
-  bool again = false;
-  if (!GetFormatInfo(&format, &visible_size, &again))
-    return false;
-
-  *endpos = size;
-
-  if (again) {
-    // Need more stream to decode format, return true and schedule next buffer.
-    return true;
-  }
-
-  // Run this initialization only on first startup.
-  if (decoder_state_ == kInitialized) {
-    DVLOG(3) << "DecodeBufferInitial(): running initialization";
-    // Success! Setup our parameters.
-    if (!CreateBuffersForFormat(format, visible_size))
-      return false;
-  }
-
-  decoder_state_ = kDecoding;
-  ScheduleDecodeBufferTaskIfNeeded();
-  return true;
-}
-
-bool V4L2VideoDecodeAccelerator::DecodeBufferContinue(
-    const void* data, size_t size) {
-  DVLOG(3) << "DecodeBufferContinue(): data=" << data << ", size=" << size;
-  DCHECK_EQ(decoder_thread_.message_loop(), base::MessageLoop::current());
-  DCHECK_EQ(decoder_state_, kDecoding);
-
-  // Both of these calls will set kError state if they fail.
-  // Only flush the frame if it's complete.
-  return (AppendToInputFrame(data, size) &&
-          (decoder_partial_frame_pending_ || FlushInputFrame()));
-}
-
-bool V4L2VideoDecodeAccelerator::AppendToInputFrame(
-    const void* data, size_t size) {
-  DVLOG(3) << "AppendToInputFrame()";
-  DCHECK_EQ(decoder_thread_.message_loop(), base::MessageLoop::current());
-  DCHECK_NE(decoder_state_, kUninitialized);
-  DCHECK_NE(decoder_state_, kResetting);
-  DCHECK_NE(decoder_state_, kError);
-  // This routine can handle data == NULL and size == 0, which occurs when
-  // we queue an empty buffer for the purposes of flushing the pipe.
-
-  // Flush if we're too big
-  if (decoder_current_input_buffer_ != -1) {
-    InputRecord& input_record =
-        input_buffer_map_[decoder_current_input_buffer_];
-    if (input_record.bytes_used + size > input_record.length) {
-      if (!FlushInputFrame())
-        return false;
-      decoder_current_input_buffer_ = -1;
-    }
-  }
-
-  // Try to get an available input buffer
-  if (decoder_current_input_buffer_ == -1) {
-    if (free_input_buffers_.empty()) {
-      // See if we can get more free buffers from HW
-      Dequeue();
-      if (free_input_buffers_.empty()) {
-        // Nope!
-        DVLOG(2) << "AppendToInputFrame(): stalled for input buffers";
-        return false;
-      }
-    }
-    decoder_current_input_buffer_ = free_input_buffers_.back();
-    free_input_buffers_.pop_back();
-    InputRecord& input_record =
-        input_buffer_map_[decoder_current_input_buffer_];
-    DCHECK_EQ(input_record.bytes_used, 0);
-    DCHECK_EQ(input_record.input_id, -1);
-    DCHECK(decoder_current_bitstream_buffer_ != NULL);
-    input_record.input_id = decoder_current_bitstream_buffer_->input_id;
-  }
-
-  DCHECK(data != NULL || size == 0);
-  if (size == 0) {
-    // If we asked for an empty buffer, return now.  We return only after
-    // getting the next input buffer, since we might actually want an empty
-    // input buffer for flushing purposes.
-    return true;
-  }
-
-  // Copy in to the buffer.
-  InputRecord& input_record =
-      input_buffer_map_[decoder_current_input_buffer_];
-  if (size > input_record.length - input_record.bytes_used) {
-    LOG(ERROR) << "AppendToInputFrame(): over-size frame, erroring";
-    NOTIFY_ERROR(UNREADABLE_INPUT);
-    return false;
-  }
-  memcpy(reinterpret_cast<uint8_t*>(input_record.address) +
-             input_record.bytes_used,
-         data, size);
-  input_record.bytes_used += size;
-
-  return true;
-}
-
-bool V4L2VideoDecodeAccelerator::FlushInputFrame() {
-  DVLOG(3) << "FlushInputFrame()";
-  DCHECK_EQ(decoder_thread_.message_loop(), base::MessageLoop::current());
-  DCHECK_NE(decoder_state_, kUninitialized);
-  DCHECK_NE(decoder_state_, kResetting);
-  DCHECK_NE(decoder_state_, kError);
-
-  if (decoder_current_input_buffer_ == -1)
-    return true;
-
-  InputRecord& input_record =
-      input_buffer_map_[decoder_current_input_buffer_];
-  DCHECK_NE(input_record.input_id, -1);
-  DCHECK(input_record.input_id != kFlushBufferId ||
-         input_record.bytes_used == 0);
-  // * if input_id >= 0, this input buffer was prompted by a bitstream buffer we
-  //   got from the client.  We can skip it if it is empty.
-  // * if input_id < 0 (should be kFlushBufferId in this case), this input
-  //   buffer was prompted by a flush buffer, and should be queued even when
-  //   empty.
-  if (input_record.input_id >= 0 && input_record.bytes_used == 0) {
-    input_record.input_id = -1;
-    free_input_buffers_.push_back(decoder_current_input_buffer_);
-    decoder_current_input_buffer_ = -1;
-    return true;
-  }
-
-  // Queue it.
-  input_ready_queue_.push(decoder_current_input_buffer_);
-  decoder_current_input_buffer_ = -1;
-  DVLOG(3) << "FlushInputFrame(): submitting input_id="
-           << input_record.input_id;
-  // Enqueue once since there's new available input for it.
-  Enqueue();
-
-  return (decoder_state_ != kError);
-}
-
-void V4L2VideoDecodeAccelerator::ServiceDeviceTask(bool event_pending) {
-  DVLOG(3) << "ServiceDeviceTask()";
-  DCHECK_EQ(decoder_thread_.message_loop(), base::MessageLoop::current());
-  DCHECK_NE(decoder_state_, kUninitialized);
-  TRACE_EVENT0("Video Decoder", "V4L2VDA::ServiceDeviceTask");
-
-  if (decoder_state_ == kResetting) {
-    DVLOG(2) << "ServiceDeviceTask(): early out: kResetting state";
-    return;
-  } else if (decoder_state_ == kError) {
-    DVLOG(2) << "ServiceDeviceTask(): early out: kError state";
-    return;
-  } else if (decoder_state_ == kChangingResolution) {
-    DVLOG(2) << "ServiceDeviceTask(): early out: kChangingResolution state";
-    return;
-  }
-
-  bool resolution_change_pending = false;
-  if (event_pending)
-    resolution_change_pending = DequeueResolutionChangeEvent();
-  Dequeue();
-  Enqueue();
-
-  // Clear the interrupt fd.
-  if (!device_->ClearDevicePollInterrupt()) {
-    NOTIFY_ERROR(PLATFORM_FAILURE);
-    return;
-  }
-
-  bool poll_device = false;
-  // Add fd, if we should poll on it.
-  // Can be polled as soon as either input or output buffers are queued.
-  if (input_buffer_queued_count_ + output_buffer_queued_count_ > 0)
-    poll_device = true;
-
-  // ServiceDeviceTask() should only ever be scheduled from DevicePollTask(),
-  // so either:
-  // * device_poll_thread_ is running normally
-  // * device_poll_thread_ scheduled us, but then a ResetTask() or DestroyTask()
-  //   shut it down, in which case we're either in kResetting or kError states
-  //   respectively, and we should have early-outed already.
-  DCHECK(device_poll_thread_.message_loop());
-  // Queue the DevicePollTask() now.
-  device_poll_thread_.message_loop()->PostTask(
-      FROM_HERE,
-      base::Bind(&V4L2VideoDecodeAccelerator::DevicePollTask,
-                 base::Unretained(this),
-                 poll_device));
-
-  DVLOG(1) << "ServiceDeviceTask(): buffer counts: DEC["
-           << decoder_input_queue_.size() << "->"
-           << input_ready_queue_.size() << "] => DEVICE["
-           << free_input_buffers_.size() << "+"
-           << input_buffer_queued_count_ << "/"
-           << input_buffer_map_.size() << "->"
-           << free_output_buffers_.size() << "+"
-           << output_buffer_queued_count_ << "/"
-           << output_buffer_map_.size() << "] => VDA["
-           << decoder_frames_at_client_ << "]";
-
-  ScheduleDecodeBufferTaskIfNeeded();
-  if (resolution_change_pending)
-    StartResolutionChange();
-}
-
-void V4L2VideoDecodeAccelerator::Enqueue() {
-  DVLOG(3) << "Enqueue()";
-  DCHECK_EQ(decoder_thread_.message_loop(), base::MessageLoop::current());
-  DCHECK_NE(decoder_state_, kUninitialized);
-  TRACE_EVENT0("Video Decoder", "V4L2VDA::Enqueue");
-
-  // Drain the pipe of completed decode buffers.
-  const int old_inputs_queued = input_buffer_queued_count_;
-  while (!input_ready_queue_.empty()) {
-    if (!EnqueueInputRecord())
-      return;
-  }
-  if (old_inputs_queued == 0 && input_buffer_queued_count_ != 0) {
-    // We just started up a previously empty queue.
-    // Queue state changed; signal interrupt.
-    if (!device_->SetDevicePollInterrupt()) {
-      PLOG(ERROR) << "SetDevicePollInterrupt(): failed";
-      NOTIFY_ERROR(PLATFORM_FAILURE);
-      return;
-    }
-    // Start VIDIOC_STREAMON if we haven't yet.
-    if (!input_streamon_) {
-      __u32 type = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;
-      IOCTL_OR_ERROR_RETURN(VIDIOC_STREAMON, &type);
-      input_streamon_ = true;
-    }
-  }
-
-  // Enqueue all the outputs we can.
-  const int old_outputs_queued = output_buffer_queued_count_;
-  while (!free_output_buffers_.empty()) {
-    if (!EnqueueOutputRecord())
-      return;
-  }
-  if (old_outputs_queued == 0 && output_buffer_queued_count_ != 0) {
-    // We just started up a previously empty queue.
-    // Queue state changed; signal interrupt.
-    if (!device_->SetDevicePollInterrupt()) {
-      PLOG(ERROR) << "SetDevicePollInterrupt(): failed";
-      NOTIFY_ERROR(PLATFORM_FAILURE);
-      return;
-    }
-    // Start VIDIOC_STREAMON if we haven't yet.
-    if (!output_streamon_) {
-      __u32 type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
-      IOCTL_OR_ERROR_RETURN(VIDIOC_STREAMON, &type);
-      output_streamon_ = true;
-    }
-  }
-}
-
-bool V4L2VideoDecodeAccelerator::DequeueResolutionChangeEvent() {
-  DCHECK_EQ(decoder_thread_.message_loop(), base::MessageLoop::current());
-  DCHECK_NE(decoder_state_, kUninitialized);
-  DVLOG(3) << "DequeueResolutionChangeEvent()";
-
-  struct v4l2_event ev;
-  memset(&ev, 0, sizeof(ev));
-
-  while (device_->Ioctl(VIDIOC_DQEVENT, &ev) == 0) {
-    if (ev.type == V4L2_EVENT_SOURCE_CHANGE) {
-      if (ev.u.src_change.changes & V4L2_EVENT_SRC_CH_RESOLUTION) {
-        DVLOG(3)
-            << "DequeueResolutionChangeEvent(): got resolution change event.";
-        return true;
-      }
-    } else {
-      LOG(ERROR) << "DequeueResolutionChangeEvent(): got an event (" << ev.type
-                 << ") we haven't subscribed to.";
-    }
-  }
-  return false;
-}
-
-void V4L2VideoDecodeAccelerator::Dequeue() {
-  DVLOG(3) << "Dequeue()";
-  DCHECK_EQ(decoder_thread_.message_loop(), base::MessageLoop::current());
-  DCHECK_NE(decoder_state_, kUninitialized);
-  TRACE_EVENT0("Video Decoder", "V4L2VDA::Dequeue");
-
-  // Dequeue completed input (VIDEO_OUTPUT) buffers, and recycle to the free
-  // list.
-  while (input_buffer_queued_count_ > 0) {
-    DCHECK(input_streamon_);
-    struct v4l2_buffer dqbuf;
-    struct v4l2_plane planes[1];
-    memset(&dqbuf, 0, sizeof(dqbuf));
-    memset(planes, 0, sizeof(planes));
-    dqbuf.type   = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;
-    dqbuf.memory = V4L2_MEMORY_MMAP;
-    dqbuf.m.planes = planes;
-    dqbuf.length = 1;
-    if (device_->Ioctl(VIDIOC_DQBUF, &dqbuf) != 0) {
-      if (errno == EAGAIN) {
-        // EAGAIN if we're just out of buffers to dequeue.
-        break;
-      }
-      PLOG(ERROR) << "Dequeue(): ioctl() failed: VIDIOC_DQBUF";
-      NOTIFY_ERROR(PLATFORM_FAILURE);
-      return;
-    }
-    InputRecord& input_record = input_buffer_map_[dqbuf.index];
-    DCHECK(input_record.at_device);
-    free_input_buffers_.push_back(dqbuf.index);
-    input_record.at_device = false;
-    input_record.bytes_used = 0;
-    input_record.input_id = -1;
-    input_buffer_queued_count_--;
-  }
-
-  // Dequeue completed output (VIDEO_CAPTURE) buffers, and queue to the
-  // completed queue.
-  while (output_buffer_queued_count_ > 0) {
-    DCHECK(output_streamon_);
-    struct v4l2_buffer dqbuf;
-    std::unique_ptr<struct v4l2_plane[]> planes(
-        new v4l2_plane[output_planes_count_]);
-    memset(&dqbuf, 0, sizeof(dqbuf));
-    memset(planes.get(), 0, sizeof(struct v4l2_plane) * output_planes_count_);
-    dqbuf.type   = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
-    dqbuf.memory = V4L2_MEMORY_MMAP;
-    dqbuf.m.planes = planes.get();
-    dqbuf.length = output_planes_count_;
-    if (device_->Ioctl(VIDIOC_DQBUF, &dqbuf) != 0) {
-      if (errno == EAGAIN) {
-        // EAGAIN if we're just out of buffers to dequeue.
-        break;
-      }
-      PLOG(ERROR) << "Dequeue(): ioctl() failed: VIDIOC_DQBUF";
-      NOTIFY_ERROR(PLATFORM_FAILURE);
-      return;
-    }
-    OutputRecord& output_record = output_buffer_map_[dqbuf.index];
-    DCHECK(output_record.at_device);
-    DCHECK(!output_record.at_client);
-    DCHECK_NE(output_record.egl_image, EGL_NO_IMAGE_KHR);
-    DCHECK_NE(output_record.picture_id, -1);
-    output_record.at_device = false;
-    if (dqbuf.m.planes[0].bytesused == 0) {
-      // This is an empty output buffer returned as part of a flush.
-      free_output_buffers_.push(dqbuf.index);
-    } else {
-      DCHECK_GE(dqbuf.timestamp.tv_sec, 0);
-      output_record.at_client = true;
-      DVLOG(3) << "Dequeue(): returning input_id=" << dqbuf.timestamp.tv_sec
-               << " as picture_id=" << output_record.picture_id;
-      const media::Picture& picture =
-          media::Picture(output_record.picture_id, dqbuf.timestamp.tv_sec,
-                         gfx::Rect(visible_size_), false);
-      pending_picture_ready_.push(
-          PictureRecord(output_record.cleared, picture));
-      SendPictureReady();
-      output_record.cleared = true;
-      decoder_frames_at_client_++;
-    }
-    output_buffer_queued_count_--;
-  }
-
-  NotifyFlushDoneIfNeeded();
-}
-
-bool V4L2VideoDecodeAccelerator::EnqueueInputRecord() {
-  DVLOG(3) << "EnqueueInputRecord()";
-  DCHECK(!input_ready_queue_.empty());
-
-  // Enqueue an input (VIDEO_OUTPUT) buffer.
-  const int buffer = input_ready_queue_.front();
-  InputRecord& input_record = input_buffer_map_[buffer];
-  DCHECK(!input_record.at_device);
-  struct v4l2_buffer qbuf;
-  struct v4l2_plane qbuf_plane;
-  memset(&qbuf, 0, sizeof(qbuf));
-  memset(&qbuf_plane, 0, sizeof(qbuf_plane));
-  qbuf.index                 = buffer;
-  qbuf.type                  = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;
-  qbuf.timestamp.tv_sec      = input_record.input_id;
-  qbuf.memory                = V4L2_MEMORY_MMAP;
-  qbuf.m.planes              = &qbuf_plane;
-  qbuf.m.planes[0].bytesused = input_record.bytes_used;
-  qbuf.length                = 1;
-  IOCTL_OR_ERROR_RETURN_FALSE(VIDIOC_QBUF, &qbuf);
-  input_ready_queue_.pop();
-  input_record.at_device = true;
-  input_buffer_queued_count_++;
-  DVLOG(3) << "EnqueueInputRecord(): enqueued input_id="
-           << input_record.input_id << " size="  << input_record.bytes_used;
-  return true;
-}
-
-bool V4L2VideoDecodeAccelerator::EnqueueOutputRecord() {
-  DVLOG(3) << "EnqueueOutputRecord()";
-  DCHECK(!free_output_buffers_.empty());
-
-  // Enqueue an output (VIDEO_CAPTURE) buffer.
-  const int buffer = free_output_buffers_.front();
-  OutputRecord& output_record = output_buffer_map_[buffer];
-  DCHECK(!output_record.at_device);
-  DCHECK(!output_record.at_client);
-  DCHECK_NE(output_record.egl_image, EGL_NO_IMAGE_KHR);
-  DCHECK_NE(output_record.picture_id, -1);
-  if (output_record.egl_sync != EGL_NO_SYNC_KHR) {
-    TRACE_EVENT0("Video Decoder",
-                 "V4L2VDA::EnqueueOutputRecord: eglClientWaitSyncKHR");
-    // If we have to wait for completion, wait.  Note that
-    // free_output_buffers_ is a FIFO queue, so we always wait on the
-    // buffer that has been in the queue the longest.
-    if (eglClientWaitSyncKHR(egl_display_, output_record.egl_sync, 0,
-                             EGL_FOREVER_KHR) == EGL_FALSE) {
-      // This will cause tearing, but is safe otherwise.
-      DVLOG(1) << __func__ << " eglClientWaitSyncKHR failed!";
-    }
-    if (eglDestroySyncKHR(egl_display_, output_record.egl_sync) != EGL_TRUE) {
-      LOG(ERROR) << __func__ << " eglDestroySyncKHR failed!";
-      NOTIFY_ERROR(PLATFORM_FAILURE);
-      return false;
-    }
-    output_record.egl_sync = EGL_NO_SYNC_KHR;
-  }
-  struct v4l2_buffer qbuf;
-  std::unique_ptr<struct v4l2_plane[]> qbuf_planes(
-      new v4l2_plane[output_planes_count_]);
-  memset(&qbuf, 0, sizeof(qbuf));
-  memset(
-      qbuf_planes.get(), 0, sizeof(struct v4l2_plane) * output_planes_count_);
-  qbuf.index    = buffer;
-  qbuf.type     = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
-  qbuf.memory   = V4L2_MEMORY_MMAP;
-  qbuf.m.planes = qbuf_planes.get();
-  qbuf.length = output_planes_count_;
-  IOCTL_OR_ERROR_RETURN_FALSE(VIDIOC_QBUF, &qbuf);
-  free_output_buffers_.pop();
-  output_record.at_device = true;
-  output_buffer_queued_count_++;
-  return true;
-}
-
-void V4L2VideoDecodeAccelerator::ReusePictureBufferTask(
-    int32_t picture_buffer_id,
-    std::unique_ptr<EGLSyncKHRRef> egl_sync_ref) {
-  DVLOG(3) << "ReusePictureBufferTask(): picture_buffer_id="
-           << picture_buffer_id;
-  DCHECK_EQ(decoder_thread_.message_loop(), base::MessageLoop::current());
-  TRACE_EVENT0("Video Decoder", "V4L2VDA::ReusePictureBufferTask");
-
-  // We run ReusePictureBufferTask even if we're in kResetting.
-  if (decoder_state_ == kError) {
-    DVLOG(2) << "ReusePictureBufferTask(): early out: kError state";
-    return;
-  }
-
-  if (decoder_state_ == kChangingResolution) {
-    DVLOG(2) << "ReusePictureBufferTask(): early out: kChangingResolution";
-    return;
-  }
-
-  size_t index;
-  for (index = 0; index < output_buffer_map_.size(); ++index)
-    if (output_buffer_map_[index].picture_id == picture_buffer_id)
-      break;
-
-  if (index >= output_buffer_map_.size()) {
-    // It's possible that we've already posted a DismissPictureBuffer for this
-    // picture, but it has not yet executed when this ReusePictureBuffer was
-    // posted to us by the client. In that case just ignore this (we've already
-    // dismissed it and accounted for that) and let the sync object get
-    // destroyed.
-    DVLOG(4) << "ReusePictureBufferTask(): got picture id= "
-             << picture_buffer_id << " not in use (anymore?).";
-    return;
-  }
-
-  OutputRecord& output_record = output_buffer_map_[index];
-  if (output_record.at_device || !output_record.at_client) {
-    LOG(ERROR) << "ReusePictureBufferTask(): picture_buffer_id not reusable";
-    NOTIFY_ERROR(INVALID_ARGUMENT);
-    return;
-  }
-
-  DCHECK_EQ(output_record.egl_sync, EGL_NO_SYNC_KHR);
-  DCHECK(!output_record.at_device);
-  output_record.at_client = false;
-  output_record.egl_sync = egl_sync_ref->egl_sync;
-  free_output_buffers_.push(index);
-  decoder_frames_at_client_--;
-  // Take ownership of the EGLSync.
-  egl_sync_ref->egl_sync = EGL_NO_SYNC_KHR;
-  // We got a buffer back, so enqueue it back.
-  Enqueue();
-}
-
-void V4L2VideoDecodeAccelerator::FlushTask() {
-  DVLOG(3) << "FlushTask()";
-  DCHECK_EQ(decoder_thread_.message_loop(), base::MessageLoop::current());
-  TRACE_EVENT0("Video Decoder", "V4L2VDA::FlushTask");
-
-  // Flush outstanding buffers.
-  if (decoder_state_ == kInitialized || decoder_state_ == kAfterReset) {
-    // There's nothing in the pipe, so return done immediately.
-    DVLOG(3) << "FlushTask(): returning flush";
-    child_task_runner_->PostTask(FROM_HERE,
-                                 base::Bind(&Client::NotifyFlushDone, client_));
-    return;
-  } else if (decoder_state_ == kError) {
-    DVLOG(2) << "FlushTask(): early out: kError state";
-    return;
-  }
-
-  // We don't support stacked flushing.
-  DCHECK(!decoder_flushing_);
-
-  // Queue up an empty buffer -- this triggers the flush.
-  decoder_input_queue_.push(
-      linked_ptr<BitstreamBufferRef>(new BitstreamBufferRef(
-          decode_client_, decode_task_runner_, nullptr, kFlushBufferId)));
-  decoder_flushing_ = true;
-  SendPictureReady();  // Send all pending PictureReady.
-
-  ScheduleDecodeBufferTaskIfNeeded();
-}
-
-void V4L2VideoDecodeAccelerator::NotifyFlushDoneIfNeeded() {
-  if (!decoder_flushing_)
-    return;
-
-  // Pipeline is empty when:
-  // * Decoder input queue is empty of non-delayed buffers.
-  // * There is no currently filling input buffer.
-  // * Input holding queue is empty.
-  // * All input (VIDEO_OUTPUT) buffers are returned.
-  if (!decoder_input_queue_.empty()) {
-    if (decoder_input_queue_.front()->input_id !=
-        decoder_delay_bitstream_buffer_id_)
-      return;
-  }
-  if (decoder_current_input_buffer_ != -1)
-    return;
-  if ((input_ready_queue_.size() + input_buffer_queued_count_) != 0)
-    return;
-
-  // TODO(posciak): crbug.com/270039. Exynos requires a streamoff-streamon
-  // sequence after flush to continue, even if we are not resetting. This would
-  // make sense, because we don't really want to resume from a non-resume point
-  // (e.g. not from an IDR) if we are flushed.
-  // MSE player however triggers a Flush() on chunk end, but never Reset(). One
-  // could argue either way, or even say that Flush() is not needed/harmful when
-  // transitioning to next chunk.
-  // For now, do the streamoff-streamon cycle to satisfy Exynos and not freeze
-  // when doing MSE. This should be harmless otherwise.
-  if (!(StopDevicePoll() && StopOutputStream() && StopInputStream()))
-    return;
-
-  if (!StartDevicePoll())
-    return;
-
-  decoder_delay_bitstream_buffer_id_ = -1;
-  decoder_flushing_ = false;
-  DVLOG(3) << "NotifyFlushDoneIfNeeded(): returning flush";
-  child_task_runner_->PostTask(FROM_HERE,
-                               base::Bind(&Client::NotifyFlushDone, client_));
-
-  // While we were flushing, we early-outed DecodeBufferTask()s.
-  ScheduleDecodeBufferTaskIfNeeded();
-}
-
-void V4L2VideoDecodeAccelerator::ResetTask() {
-  DVLOG(3) << "ResetTask()";
-  DCHECK_EQ(decoder_thread_.message_loop(), base::MessageLoop::current());
-  TRACE_EVENT0("Video Decoder", "V4L2VDA::ResetTask");
-
-  if (decoder_state_ == kError) {
-    DVLOG(2) << "ResetTask(): early out: kError state";
-    return;
-  }
-
-  // If we are in the middle of switching resolutions, postpone reset until
-  // it's done. We don't have to worry about timing of this wrt to decoding,
-  // because output pipe is already stopped if we are changing resolution.
-  // We will come back here after we are done with the resolution change.
-  DCHECK(!resolution_change_reset_pending_);
-  if (decoder_state_ == kChangingResolution) {
-    resolution_change_reset_pending_ = true;
-    return;
-  }
-
-  // After the output stream is stopped, the codec should not post any
-  // resolution change events. So we dequeue the resolution change event
-  // afterwards. The event could be posted before or while stopping the output
-  // stream. The codec will expect the buffer of new size after the seek, so
-  // we need to handle the resolution change event first.
-  if (!(StopDevicePoll() && StopOutputStream()))
-    return;
-
-  if (DequeueResolutionChangeEvent()) {
-    resolution_change_reset_pending_ = true;
-    StartResolutionChange();
-    return;
-  }
-
-  if (!StopInputStream())
-    return;
-
-  decoder_current_bitstream_buffer_.reset();
-  while (!decoder_input_queue_.empty())
-    decoder_input_queue_.pop();
-
-  decoder_current_input_buffer_ = -1;
-
-  // If we were flushing, we'll never return any more BitstreamBuffers or
-  // PictureBuffers; they have all been dropped and returned by now.
-  NotifyFlushDoneIfNeeded();
-
-  // Mark that we're resetting, then enqueue a ResetDoneTask().  All intervening
-  // jobs will early-out in the kResetting state.
-  decoder_state_ = kResetting;
-  SendPictureReady();  // Send all pending PictureReady.
-  decoder_thread_.message_loop()->PostTask(FROM_HERE, base::Bind(
-      &V4L2VideoDecodeAccelerator::ResetDoneTask, base::Unretained(this)));
-}
-
-void V4L2VideoDecodeAccelerator::ResetDoneTask() {
-  DVLOG(3) << "ResetDoneTask()";
-  DCHECK_EQ(decoder_thread_.message_loop(), base::MessageLoop::current());
-  TRACE_EVENT0("Video Decoder", "V4L2VDA::ResetDoneTask");
-
-  if (decoder_state_ == kError) {
-    DVLOG(2) << "ResetDoneTask(): early out: kError state";
-    return;
-  }
-
-  if (!StartDevicePoll())
-    return;
-
-  // Reset format-specific bits.
-  if (video_profile_ >= media::H264PROFILE_MIN &&
-      video_profile_ <= media::H264PROFILE_MAX) {
-    decoder_h264_parser_.reset(new media::H264Parser());
-  }
-
-  // Jobs drained, we're finished resetting.
-  DCHECK_EQ(decoder_state_, kResetting);
-  if (output_buffer_map_.empty()) {
-    // We must have gotten Reset() before we had a chance to request buffers
-    // from the client.
-    decoder_state_ = kInitialized;
-  } else {
-    decoder_state_ = kAfterReset;
-  }
-
-  decoder_partial_frame_pending_ = false;
-  decoder_delay_bitstream_buffer_id_ = -1;
-  child_task_runner_->PostTask(FROM_HERE,
-                               base::Bind(&Client::NotifyResetDone, client_));
-
-  // While we were resetting, we early-outed DecodeBufferTask()s.
-  ScheduleDecodeBufferTaskIfNeeded();
-}
-
-void V4L2VideoDecodeAccelerator::DestroyTask() {
-  DVLOG(3) << "DestroyTask()";
-  TRACE_EVENT0("Video Decoder", "V4L2VDA::DestroyTask");
-
-  // DestroyTask() should run regardless of decoder_state_.
-
-  StopDevicePoll();
-  StopOutputStream();
-  StopInputStream();
-
-  decoder_current_bitstream_buffer_.reset();
-  decoder_current_input_buffer_ = -1;
-  decoder_decode_buffer_tasks_scheduled_ = 0;
-  decoder_frames_at_client_ = 0;
-  while (!decoder_input_queue_.empty())
-    decoder_input_queue_.pop();
-  decoder_flushing_ = false;
-
-  // Set our state to kError.  Just in case.
-  decoder_state_ = kError;
-}
-
-bool V4L2VideoDecodeAccelerator::StartDevicePoll() {
-  DVLOG(3) << "StartDevicePoll()";
-  DCHECK(!device_poll_thread_.IsRunning());
-  DCHECK_EQ(decoder_thread_.message_loop(), base::MessageLoop::current());
-
-  // Start up the device poll thread and schedule its first DevicePollTask().
-  if (!device_poll_thread_.Start()) {
-    LOG(ERROR) << "StartDevicePoll(): Device thread failed to start";
-    NOTIFY_ERROR(PLATFORM_FAILURE);
-    return false;
-  }
-  device_poll_thread_.message_loop()->PostTask(FROM_HERE, base::Bind(
-      &V4L2VideoDecodeAccelerator::DevicePollTask,
-      base::Unretained(this),
-      0));
-
-  return true;
-}
-
-bool V4L2VideoDecodeAccelerator::StopDevicePoll() {
-  DVLOG(3) << "StopDevicePoll()";
-
-  if (!device_poll_thread_.IsRunning())
-    return true;
-
-  if (decoder_thread_.IsRunning())
-    DCHECK_EQ(decoder_thread_.message_loop(), base::MessageLoop::current());
-
-  // Signal the DevicePollTask() to stop, and stop the device poll thread.
-  if (!device_->SetDevicePollInterrupt()) {
-    PLOG(ERROR) << "SetDevicePollInterrupt(): failed";
-    NOTIFY_ERROR(PLATFORM_FAILURE);
-    return false;
-  }
-  device_poll_thread_.Stop();
-  // Clear the interrupt now, to be sure.
-  if (!device_->ClearDevicePollInterrupt()) {
-    NOTIFY_ERROR(PLATFORM_FAILURE);
-    return false;
-  }
-  DVLOG(3) << "StopDevicePoll(): device poll stopped";
-  return true;
-}
-
-bool V4L2VideoDecodeAccelerator::StopOutputStream() {
-  DVLOG(3) << "StopOutputStream()";
-  if (!output_streamon_)
-    return true;
-
-  __u32 type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
-  IOCTL_OR_ERROR_RETURN_FALSE(VIDIOC_STREAMOFF, &type);
-  output_streamon_ = false;
-
-  // Reset accounting info for output.
-  while (!free_output_buffers_.empty())
-    free_output_buffers_.pop();
-
-  for (size_t i = 0; i < output_buffer_map_.size(); ++i) {
-    OutputRecord& output_record = output_buffer_map_[i];
-    DCHECK(!(output_record.at_client && output_record.at_device));
-
-    // After streamoff, the device drops ownership of all buffers, even if
-    // we don't dequeue them explicitly.
-    output_buffer_map_[i].at_device = false;
-    // Some of them may still be owned by the client however.
-    // Reuse only those that aren't.
-    if (!output_record.at_client) {
-      DCHECK_EQ(output_record.egl_sync, EGL_NO_SYNC_KHR);
-      free_output_buffers_.push(i);
-    }
-  }
-  output_buffer_queued_count_ = 0;
-  return true;
-}
-
-bool V4L2VideoDecodeAccelerator::StopInputStream() {
-  DVLOG(3) << "StopInputStream()";
-  if (!input_streamon_)
-    return true;
-
-  __u32 type = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;
-  IOCTL_OR_ERROR_RETURN_FALSE(VIDIOC_STREAMOFF, &type);
-  input_streamon_ = false;
-
-  // Reset accounting info for input.
-  while (!input_ready_queue_.empty())
-    input_ready_queue_.pop();
-  free_input_buffers_.clear();
-  for (size_t i = 0; i < input_buffer_map_.size(); ++i) {
-    free_input_buffers_.push_back(i);
-    input_buffer_map_[i].at_device = false;
-    input_buffer_map_[i].bytes_used = 0;
-    input_buffer_map_[i].input_id = -1;
-  }
-  input_buffer_queued_count_ = 0;
-
-  return true;
-}
-
-void V4L2VideoDecodeAccelerator::StartResolutionChange() {
-  DCHECK_EQ(decoder_thread_.message_loop(), base::MessageLoop::current());
-  DCHECK_NE(decoder_state_, kUninitialized);
-  DCHECK_NE(decoder_state_, kResetting);
-
-  DVLOG(3) << "Initiate resolution change";
-
-  if (!(StopDevicePoll() && StopOutputStream()))
-    return;
-
-  decoder_state_ = kChangingResolution;
-
-  // Post a task to clean up buffers on child thread. This will also ensure
-  // that we won't accept ReusePictureBuffer() anymore after that.
-  child_task_runner_->PostTask(
-      FROM_HERE,
-      base::Bind(&V4L2VideoDecodeAccelerator::ResolutionChangeDestroyBuffers,
-                 weak_this_));
-}
-
-void V4L2VideoDecodeAccelerator::FinishResolutionChange() {
-  DCHECK_EQ(decoder_thread_.message_loop(), base::MessageLoop::current());
-  DCHECK_EQ(decoder_state_, kChangingResolution);
-  DVLOG(3) << "FinishResolutionChange()";
-
-  if (decoder_state_ == kError) {
-    DVLOG(2) << "FinishResolutionChange(): early out: kError state";
-    return;
-  }
-
-  struct v4l2_format format;
-  bool again;
-  gfx::Size visible_size;
-  bool ret = GetFormatInfo(&format, &visible_size, &again);
-  if (!ret || again) {
-    LOG(ERROR) << "Couldn't get format information after resolution change";
-    NOTIFY_ERROR(PLATFORM_FAILURE);
-    return;
-  }
-
-  if (!CreateBuffersForFormat(format, visible_size)) {
-    LOG(ERROR) << "Couldn't reallocate buffers after resolution change";
-    NOTIFY_ERROR(PLATFORM_FAILURE);
-    return;
-  }
-
-  decoder_state_ = kDecoding;
-
-  if (resolution_change_reset_pending_) {
-    resolution_change_reset_pending_ = false;
-    ResetTask();
-    return;
-  }
-
-  if (!StartDevicePoll())
-    return;
-
-  Enqueue();
-  ScheduleDecodeBufferTaskIfNeeded();
-}
-
-void V4L2VideoDecodeAccelerator::DevicePollTask(bool poll_device) {
-  DVLOG(3) << "DevicePollTask()";
-  DCHECK_EQ(device_poll_thread_.message_loop(), base::MessageLoop::current());
-  TRACE_EVENT0("Video Decoder", "V4L2VDA::DevicePollTask");
-
-  bool event_pending = false;
-
-  if (!device_->Poll(poll_device, &event_pending)) {
-    NOTIFY_ERROR(PLATFORM_FAILURE);
-    return;
-  }
-
-  // All processing should happen on ServiceDeviceTask(), since we shouldn't
-  // touch decoder state from this thread.
-  decoder_thread_.message_loop()->PostTask(FROM_HERE, base::Bind(
-      &V4L2VideoDecodeAccelerator::ServiceDeviceTask,
-      base::Unretained(this), event_pending));
-}
-
-void V4L2VideoDecodeAccelerator::NotifyError(Error error) {
-  DVLOG(2) << "NotifyError()";
-
-  if (!child_task_runner_->BelongsToCurrentThread()) {
-    child_task_runner_->PostTask(
-        FROM_HERE, base::Bind(&V4L2VideoDecodeAccelerator::NotifyError,
-                              weak_this_, error));
-    return;
-  }
-
-  if (client_) {
-    client_->NotifyError(error);
-    client_ptr_factory_.reset();
-  }
-}
-
-void V4L2VideoDecodeAccelerator::SetErrorState(Error error) {
-  // We can touch decoder_state_ only if this is the decoder thread or the
-  // decoder thread isn't running.
-  if (decoder_thread_.message_loop() != NULL &&
-      decoder_thread_.message_loop() != base::MessageLoop::current()) {
-    decoder_thread_.message_loop()->PostTask(FROM_HERE, base::Bind(
-        &V4L2VideoDecodeAccelerator::SetErrorState,
-        base::Unretained(this), error));
-    return;
-  }
-
-  // Post NotifyError only if we are already initialized, as the API does
-  // not allow doing so before that.
-  if (decoder_state_ != kError && decoder_state_ != kUninitialized)
-    NotifyError(error);
-
-  decoder_state_ = kError;
-}
-
-bool V4L2VideoDecodeAccelerator::GetFormatInfo(struct v4l2_format* format,
-                                               gfx::Size* visible_size,
-                                               bool* again) {
-  DCHECK_EQ(decoder_thread_.message_loop(), base::MessageLoop::current());
-
-  *again = false;
-  memset(format, 0, sizeof(*format));
-  format->type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
-  if (device_->Ioctl(VIDIOC_G_FMT, format) != 0) {
-    if (errno == EINVAL) {
-      // EINVAL means we haven't seen sufficient stream to decode the format.
-      *again = true;
-      return true;
-    } else {
-      PLOG(ERROR) << __func__ << "(): ioctl() failed: VIDIOC_G_FMT";
-      NOTIFY_ERROR(PLATFORM_FAILURE);
-      return false;
-    }
-  }
-
-  // Make sure we are still getting the format we set on initialization.
-  if (format->fmt.pix_mp.pixelformat != output_format_fourcc_) {
-    LOG(ERROR) << "Unexpected format from G_FMT on output";
-    return false;
-  }
-
-  gfx::Size coded_size(format->fmt.pix_mp.width, format->fmt.pix_mp.height);
-  if (visible_size != nullptr)
-    *visible_size = GetVisibleSize(coded_size);
-
-  return true;
-}
-
-bool V4L2VideoDecodeAccelerator::CreateBuffersForFormat(
-    const struct v4l2_format& format,
-    const gfx::Size& visible_size) {
-  DCHECK_EQ(decoder_thread_.message_loop(), base::MessageLoop::current());
-  output_planes_count_ = format.fmt.pix_mp.num_planes;
-  coded_size_.SetSize(format.fmt.pix_mp.width, format.fmt.pix_mp.height);
-  visible_size_ = visible_size;
-  DVLOG(3) << "CreateBuffersForFormat(): new resolution: "
-           << coded_size_.ToString() << ", visible size: "
-           << visible_size_.ToString();
-
-  return CreateOutputBuffers();
-}
-
-gfx::Size V4L2VideoDecodeAccelerator::GetVisibleSize(
-    const gfx::Size& coded_size) {
-  DCHECK_EQ(decoder_thread_.message_loop(), base::MessageLoop::current());
-
-  struct v4l2_crop crop_arg;
-  memset(&crop_arg, 0, sizeof(crop_arg));
-  crop_arg.type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
-
-  if (device_->Ioctl(VIDIOC_G_CROP, &crop_arg) != 0) {
-    PLOG(ERROR) << "GetVisibleSize(): ioctl() VIDIOC_G_CROP failed";
-    return coded_size;
-  }
-
-  gfx::Rect rect(crop_arg.c.left, crop_arg.c.top, crop_arg.c.width,
-                 crop_arg.c.height);
-  DVLOG(3) << "visible rectangle is " << rect.ToString();
-  if (!gfx::Rect(coded_size).Contains(rect)) {
-    DLOG(ERROR) << "visible rectangle " << rect.ToString()
-                << " is not inside coded size " << coded_size.ToString();
-    return coded_size;
-  }
-  if (rect.IsEmpty()) {
-    DLOG(ERROR) << "visible size is empty";
-    return coded_size;
-  }
-
-  // Chrome assume picture frame is coded at (0, 0).
-  if (!rect.origin().IsOrigin()) {
-    DLOG(ERROR) << "Unexpected visible rectangle " << rect.ToString()
-                << ", top-left is not origin";
-    return coded_size;
-  }
-
-  return rect.size();
-}
-
-bool V4L2VideoDecodeAccelerator::CreateInputBuffers() {
-  DVLOG(3) << "CreateInputBuffers()";
-  // We always run this as we prepare to initialize.
-  DCHECK_EQ(decoder_state_, kUninitialized);
-  DCHECK(!input_streamon_);
-  DCHECK(input_buffer_map_.empty());
-
-  struct v4l2_requestbuffers reqbufs;
-  memset(&reqbufs, 0, sizeof(reqbufs));
-  reqbufs.count  = kInputBufferCount;
-  reqbufs.type   = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;
-  reqbufs.memory = V4L2_MEMORY_MMAP;
-  IOCTL_OR_ERROR_RETURN_FALSE(VIDIOC_REQBUFS, &reqbufs);
-  input_buffer_map_.resize(reqbufs.count);
-  for (size_t i = 0; i < input_buffer_map_.size(); ++i) {
-    free_input_buffers_.push_back(i);
-
-    // Query for the MEMORY_MMAP pointer.
-    struct v4l2_plane planes[1];
-    struct v4l2_buffer buffer;
-    memset(&buffer, 0, sizeof(buffer));
-    memset(planes, 0, sizeof(planes));
-    buffer.index    = i;
-    buffer.type     = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;
-    buffer.memory   = V4L2_MEMORY_MMAP;
-    buffer.m.planes = planes;
-    buffer.length   = 1;
-    IOCTL_OR_ERROR_RETURN_FALSE(VIDIOC_QUERYBUF, &buffer);
-    void* address = device_->Mmap(NULL,
-                                  buffer.m.planes[0].length,
-                                  PROT_READ | PROT_WRITE,
-                                  MAP_SHARED,
-                                  buffer.m.planes[0].m.mem_offset);
-    if (address == MAP_FAILED) {
-      PLOG(ERROR) << "CreateInputBuffers(): mmap() failed";
-      return false;
-    }
-    input_buffer_map_[i].address = address;
-    input_buffer_map_[i].length = buffer.m.planes[0].length;
-  }
-
-  return true;
-}
-
-bool V4L2VideoDecodeAccelerator::SetupFormats() {
-  // We always run this as we prepare to initialize.
-  DCHECK_EQ(decoder_state_, kUninitialized);
-  DCHECK(!input_streamon_);
-  DCHECK(!output_streamon_);
-
-  __u32 input_format_fourcc =
-      V4L2Device::VideoCodecProfileToV4L2PixFmt(video_profile_, false);
-  if (!input_format_fourcc) {
-    NOTREACHED();
-    return false;
-  }
-
-  size_t input_size;
-  gfx::Size max_resolution, min_resolution;
-  device_->GetSupportedResolution(input_format_fourcc, &min_resolution,
-                                  &max_resolution);
-  if (max_resolution.width() > 1920 && max_resolution.height() > 1088)
-    input_size = kInputBufferMaxSizeFor4k;
-  else
-    input_size = kInputBufferMaxSizeFor1080p;
-
-  struct v4l2_fmtdesc fmtdesc;
-  memset(&fmtdesc, 0, sizeof(fmtdesc));
-  fmtdesc.type = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;
-  bool is_format_supported = false;
-  while (device_->Ioctl(VIDIOC_ENUM_FMT, &fmtdesc) == 0) {
-    if (fmtdesc.pixelformat == input_format_fourcc) {
-      is_format_supported = true;
-      break;
-    }
-    ++fmtdesc.index;
-  }
-
-  if (!is_format_supported) {
-    DVLOG(1) << "Input fourcc " << input_format_fourcc
-             << " not supported by device.";
-    return false;
-  }
-
-  struct v4l2_format format;
-  memset(&format, 0, sizeof(format));
-  format.type = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;
-  format.fmt.pix_mp.pixelformat = input_format_fourcc;
-  format.fmt.pix_mp.plane_fmt[0].sizeimage = input_size;
-  format.fmt.pix_mp.num_planes = 1;
-  IOCTL_OR_ERROR_RETURN_FALSE(VIDIOC_S_FMT, &format);
-
-  // We have to set up the format for output, because the driver may not allow
-  // changing it once we start streaming; whether it can support our chosen
-  // output format or not may depend on the input format.
-  memset(&fmtdesc, 0, sizeof(fmtdesc));
-  fmtdesc.type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
-  while (device_->Ioctl(VIDIOC_ENUM_FMT, &fmtdesc) == 0) {
-    if (device_->CanCreateEGLImageFrom(fmtdesc.pixelformat)) {
-      output_format_fourcc_ = fmtdesc.pixelformat;
-      break;
-    }
-    ++fmtdesc.index;
-  }
-
-  if (output_format_fourcc_ == 0) {
-    LOG(ERROR) << "Could not find a usable output format";
-    return false;
-  }
-
-  // Just set the fourcc for output; resolution, etc., will come from the
-  // driver once it extracts it from the stream.
-  memset(&format, 0, sizeof(format));
-  format.type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
-  format.fmt.pix_mp.pixelformat = output_format_fourcc_;
-  IOCTL_OR_ERROR_RETURN_FALSE(VIDIOC_S_FMT, &format);
-
-  return true;
-}
-
-bool V4L2VideoDecodeAccelerator::CreateOutputBuffers() {
-  DVLOG(3) << "CreateOutputBuffers()";
-  DCHECK(decoder_state_ == kInitialized ||
-         decoder_state_ == kChangingResolution);
-  DCHECK(!output_streamon_);
-  DCHECK(output_buffer_map_.empty());
-
-  // Number of output buffers we need.
-  struct v4l2_control ctrl;
-  memset(&ctrl, 0, sizeof(ctrl));
-  ctrl.id = V4L2_CID_MIN_BUFFERS_FOR_CAPTURE;
-  IOCTL_OR_ERROR_RETURN_FALSE(VIDIOC_G_CTRL, &ctrl);
-  output_dpb_size_ = ctrl.value;
-
-  // Output format setup in Initialize().
-
-  const uint32_t buffer_count = output_dpb_size_ + kDpbOutputBufferExtraCount;
-  DVLOG(3) << "CreateOutputBuffers(): ProvidePictureBuffers(): "
-           << "buffer_count=" << buffer_count
-           << ", coded_size=" << coded_size_.ToString();
-  child_task_runner_->PostTask(
-      FROM_HERE,
-      base::Bind(&Client::ProvidePictureBuffers, client_, buffer_count, 1,
-                 coded_size_, device_->GetTextureTarget()));
-
-  // Wait for the client to call AssignPictureBuffers() on the Child thread.
-  // We do this, because if we continue decoding without finishing buffer
-  // allocation, we may end up Resetting before AssignPictureBuffers arrives,
-  // resulting in unnecessary complications and subtle bugs.
-  // For example, if the client calls Decode(Input1), Reset(), Decode(Input2)
-  // in a sequence, and Decode(Input1) results in us getting here and exiting
-  // without waiting, we might end up running Reset{,Done}Task() before
-  // AssignPictureBuffers is scheduled, thus cleaning up and pushing buffers
-  // to the free_output_buffers_ map twice. If we somehow marked buffers as
-  // not ready, we'd need special handling for restarting the second Decode
-  // task and delaying it anyway.
-  // Waiting here is not very costly and makes reasoning about different
-  // situations much simpler.
-  pictures_assigned_.Wait();
-
-  Enqueue();
-  return true;
-}
-
-void V4L2VideoDecodeAccelerator::DestroyInputBuffers() {
-  DVLOG(3) << "DestroyInputBuffers()";
-  DCHECK(child_task_runner_->BelongsToCurrentThread());
-  DCHECK(!input_streamon_);
-
-  for (size_t i = 0; i < input_buffer_map_.size(); ++i) {
-    if (input_buffer_map_[i].address != NULL) {
-      device_->Munmap(input_buffer_map_[i].address,
-                      input_buffer_map_[i].length);
-    }
-  }
-
-  struct v4l2_requestbuffers reqbufs;
-  memset(&reqbufs, 0, sizeof(reqbufs));
-  reqbufs.count = 0;
-  reqbufs.type = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;
-  reqbufs.memory = V4L2_MEMORY_MMAP;
-  IOCTL_OR_LOG_ERROR(VIDIOC_REQBUFS, &reqbufs);
-
-  input_buffer_map_.clear();
-  free_input_buffers_.clear();
-}
-
-bool V4L2VideoDecodeAccelerator::DestroyOutputBuffers() {
-  DVLOG(3) << "DestroyOutputBuffers()";
-  DCHECK(child_task_runner_->BelongsToCurrentThread());
-  DCHECK(!output_streamon_);
-  bool success = true;
-
-  for (size_t i = 0; i < output_buffer_map_.size(); ++i) {
-    OutputRecord& output_record = output_buffer_map_[i];
-
-    if (output_record.egl_image != EGL_NO_IMAGE_KHR) {
-      if (device_->DestroyEGLImage(egl_display_, output_record.egl_image) !=
-          EGL_TRUE) {
-        DVLOG(1) << __func__ << " DestroyEGLImage failed.";
-        success = false;
-      }
-    }
-
-    if (output_record.egl_sync != EGL_NO_SYNC_KHR) {
-      if (eglDestroySyncKHR(egl_display_, output_record.egl_sync) != EGL_TRUE) {
-        DVLOG(1) << __func__ << " eglDestroySyncKHR failed.";
-        success = false;
-      }
-    }
-
-    DVLOG(1) << "DestroyOutputBuffers(): dismissing PictureBuffer id="
-             << output_record.picture_id;
-    child_task_runner_->PostTask(
-        FROM_HERE, base::Bind(&Client::DismissPictureBuffer, client_,
-                              output_record.picture_id));
-  }
-
-  struct v4l2_requestbuffers reqbufs;
-  memset(&reqbufs, 0, sizeof(reqbufs));
-  reqbufs.count = 0;
-  reqbufs.type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
-  reqbufs.memory = V4L2_MEMORY_MMAP;
-  if (device_->Ioctl(VIDIOC_REQBUFS, &reqbufs) != 0) {
-    PLOG(ERROR) << "DestroyOutputBuffers() ioctl() failed: VIDIOC_REQBUFS";
-    success = false;
-  }
-
-  output_buffer_map_.clear();
-  while (!free_output_buffers_.empty())
-    free_output_buffers_.pop();
-
-  return success;
-}
-
-void V4L2VideoDecodeAccelerator::ResolutionChangeDestroyBuffers() {
-  DCHECK(child_task_runner_->BelongsToCurrentThread());
-  DVLOG(3) << "ResolutionChangeDestroyBuffers()";
-
-  if (!DestroyOutputBuffers()) {
-    LOG(ERROR) << __func__ << " Failed destroying output buffers.";
-    NOTIFY_ERROR(PLATFORM_FAILURE);
-    return;
-  }
-
-  // Finish resolution change on decoder thread.
-  decoder_thread_.message_loop()->PostTask(FROM_HERE, base::Bind(
-      &V4L2VideoDecodeAccelerator::FinishResolutionChange,
-      base::Unretained(this)));
-}
-
-void V4L2VideoDecodeAccelerator::SendPictureReady() {
-  DVLOG(3) << "SendPictureReady()";
-  DCHECK_EQ(decoder_thread_.message_loop(), base::MessageLoop::current());
-  bool resetting_or_flushing =
-      (decoder_state_ == kResetting || decoder_flushing_);
-  while (pending_picture_ready_.size() > 0) {
-    bool cleared = pending_picture_ready_.front().cleared;
-    const media::Picture& picture = pending_picture_ready_.front().picture;
-    if (cleared && picture_clearing_count_ == 0) {
-      // This picture is cleared. It can be posted to a thread different than
-      // the main GPU thread to reduce latency. This should be the case after
-      // all pictures are cleared at the beginning.
-      decode_task_runner_->PostTask(
-          FROM_HERE,
-          base::Bind(&Client::PictureReady, decode_client_, picture));
-      pending_picture_ready_.pop();
-    } else if (!cleared || resetting_or_flushing) {
-      DVLOG(3) << "SendPictureReady()"
-               << ". cleared=" << pending_picture_ready_.front().cleared
-               << ", decoder_state_=" << decoder_state_
-               << ", decoder_flushing_=" << decoder_flushing_
-               << ", picture_clearing_count_=" << picture_clearing_count_;
-      // If the picture is not cleared, post it to the child thread because it
-      // has to be cleared in the child thread. A picture only needs to be
-      // cleared once. If the decoder is resetting or flushing, send all
-      // pictures to ensure PictureReady arrive before reset or flush done.
-      child_task_runner_->PostTaskAndReply(
-          FROM_HERE, base::Bind(&Client::PictureReady, client_, picture),
-          // Unretained is safe. If Client::PictureReady gets to run, |this| is
-          // alive. Destroy() will wait the decode thread to finish.
-          base::Bind(&V4L2VideoDecodeAccelerator::PictureCleared,
-                     base::Unretained(this)));
-      picture_clearing_count_++;
-      pending_picture_ready_.pop();
-    } else {
-      // This picture is cleared. But some pictures are about to be cleared on
-      // the child thread. To preserve the order, do not send this until those
-      // pictures are cleared.
-      break;
-    }
-  }
-}
-
-void V4L2VideoDecodeAccelerator::PictureCleared() {
-  DVLOG(3) << "PictureCleared(). clearing count=" << picture_clearing_count_;
-  DCHECK_EQ(decoder_thread_.message_loop(), base::MessageLoop::current());
-  DCHECK_GT(picture_clearing_count_, 0);
-  picture_clearing_count_--;
-  SendPictureReady();
-}
-
-}  // namespace content