Always enqueue an empty buffer when flush

media/gpu/v4l2_slice_video_decode_accelerator.cc

Index: media/gpu/v4l2_slice_video_decode_accelerator.cc
diff --git a/media/gpu/v4l2_slice_video_decode_accelerator.cc b/media/gpu/v4l2_slice_video_decode_accelerator.cc
index 276c39abd9892ad20244d47597e53d298dbce9f8..a51b6f4e617f841c256f7edf0c24d10539bed0cf 100644
--- a/media/gpu/v4l2_slice_video_decode_accelerator.cc
+++ b/media/gpu/v4l2_slice_video_decode_accelerator.cc
@@ -1838,17 +1838,12 @@ void V4L2SliceVideoDecodeAccelerator::FlushTask() {
   DVLOGF(3);
   DCHECK(decoder_thread_task_runner_->BelongsToCurrentThread());
 
-  if (!decoder_input_queue_.empty()) {
-    // We are not done with pending inputs, so queue an empty buffer,
-    // which - when reached - will trigger flush sequence.
-    decoder_input_queue_.push(
-        linked_ptr<BitstreamBufferRef>(new BitstreamBufferRef(
-            decode_client_, decode_task_runner_, nullptr, kFlushBufferId)));
-    return;
-  }
-
-  // No more inputs pending, so just finish flushing here.
-  InitiateFlush();
+  // We are not done with pending inputs, so queue an empty buffer,

[Owen Lin, 2016/06/17 15:57:47]

Please also update the comment, how about:
Queue an empty buffer will trigger flush sequence after we are done with all
pending inputs.

[Pawel Osciak, 2016/06/20 00:55:53]

We actually may be done with pending inputs here already. Since the if() is
being removed, instead of checking if inputs are pending and queuing an empty
buffer only if they are, we unconditionally queue one.

How about:

"Queue an empty buffer which - when reached - will trigger the flush sequence."

[henryhsu, 2016/06/20 02:58:05]

Done.

+  // which - when reached - will trigger flush sequence.
+  decoder_input_queue_.push(
+      linked_ptr<BitstreamBufferRef>(new BitstreamBufferRef(
+          decode_client_, decode_task_runner_, nullptr, kFlushBufferId)));
+  return;

[kcwu, 2016/06/17 12:17:49]

delete this line

[Owen Lin, 2016/06/17 13:35:42]

Add one line in the end:
ScheduleDecodeBufferTaskIfNeeded()

[henryhsu, 2016/06/20 02:58:05]

Done.

[henryhsu, 2016/06/20 02:58:05]

Done.

 }
 
 void V4L2SliceVideoDecodeAccelerator::InitiateFlush() {