Add offset support to BitstreamBuffer.

content/common/gpu/media/v4l2_slice_video_decode_accelerator.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 <errno.h>
 #include <fcntl.h>
 #include <linux/videodev2.h>
 #include <poll.h>
 #include <sys/eventfd.h>
 #include <sys/ioctl.h>
@@ skipping 1172 matching lines @@
 void V4L2SliceVideoDecodeAccelerator::DecodeTask(
     const media::BitstreamBuffer& bitstream_buffer) {
   DVLOGF(3) << "input_id=" << bitstream_buffer.id()
             << " size=" << bitstream_buffer.size();
   DCHECK(decoder_thread_task_runner_->BelongsToCurrentThread());
 
   scoped_ptr<BitstreamBufferRef> bitstream_record(new BitstreamBufferRef(
       io_client_, io_task_runner_,
       new base::SharedMemory(bitstream_buffer.handle(), true),
       bitstream_buffer.size(), bitstream_buffer.id()));
-  if (!bitstream_record->shm->Map(bitstream_buffer.size())) {
+  if (!bitstream_record->shm->MapAt(bitstream_buffer.offset(),
+                                    bitstream_buffer.size())) {
     LOGF(ERROR) << "Could not map bitstream_buffer";
     NOTIFY_ERROR(UNREADABLE_INPUT);
     return;
   }
   DVLOGF(3) << "mapped at=" << bitstream_record->shm->memory();
 
   decoder_input_queue_.push(
       linked_ptr<BitstreamBufferRef>(bitstream_record.release()));
 
   ScheduleDecodeBufferTaskIfNeeded();
@@ skipping 1339 matching lines @@
   if (!device)
     return SupportedProfiles();
 
   const uint32_t supported_formats[] = {
       V4L2_PIX_FMT_H264_SLICE, V4L2_PIX_FMT_VP8_FRAME};
   return device->GetSupportedDecodeProfiles(arraysize(supported_formats),
                                             supported_formats);
 }
 
 }  // namespace content