Add an additional VDA::Flush() mode to return all allocated buffers.

content/common/gpu/media/v4l2_slice_video_decode_accelerator.cc

Index: content/common/gpu/media/v4l2_slice_video_decode_accelerator.cc
diff --git a/content/common/gpu/media/v4l2_slice_video_decode_accelerator.cc b/content/common/gpu/media/v4l2_slice_video_decode_accelerator.cc
index a338cc2672454382adf576efa46fa817e3c2c08d..a376ae295f176396c6d8cbcf24c094280f23c868 100644
--- a/content/common/gpu/media/v4l2_slice_video_decode_accelerator.cc
+++ b/content/common/gpu/media/v4l2_slice_video_decode_accelerator.cc
@@ -1623,19 +1623,21 @@ void V4L2SliceVideoDecodeAccelerator::ReusePictureBufferTask(
   surfaces_at_display_.erase(it);
 }
 
-void V4L2SliceVideoDecodeAccelerator::Flush() {
+void V4L2SliceVideoDecodeAccelerator::Flush(bool return_buffers) {
   DVLOGF(3);
   DCHECK(child_task_runner_->BelongsToCurrentThread());
 
   decoder_thread_task_runner_->PostTask(
       FROM_HERE, base::Bind(&V4L2SliceVideoDecodeAccelerator::FlushTask,
-                            base::Unretained(this)));
+                            base::Unretained(this), return_buffers));
 }
 
-void V4L2SliceVideoDecodeAccelerator::FlushTask() {
+void V4L2SliceVideoDecodeAccelerator::FlushTask(bool return_buffers) {
   DVLOGF(3);
   DCHECK(decoder_thread_task_runner_->BelongsToCurrentThread());
 
+  flush_return_all_buffers_ = return_buffers;
+
   if (!decoder_input_queue_.empty()) {
     // We are not done with pending inputs, so queue an empty buffer,
     // which - when reached - will trigger flush sequence.
@@ -1697,14 +1699,25 @@ bool V4L2SliceVideoDecodeAccelerator::FinishFlush() {
   // out of hardware. There can be no other owners of input buffers.
   DCHECK_EQ(free_input_buffers_.size(), input_buffer_map_.size());
 
-  SendPictureReady();
+  if (flush_return_all_buffers_) {
+    for (auto& output : free_output_buffers_) {
+      scoped_refptr<V4L2DecodeSurface> dec_surface = new V4L2DecodeSurface(
+          -1, -1, output,
+          base::Bind(&V4L2SliceVideoDecodeAccelerator::ReuseOutputBuffer,
+                     base::Unretained(this)));
+      OutputSurface(dec_surface);
+    }
+
+    free_output_buffers_.clear();
+  }
 
   decoder_flushing_ = false;
+  flush_return_all_buffers_ = false;
+
   DVLOGF(3) << "Flush finished";
 
   child_task_runner_->PostTask(FROM_HERE,
                                base::Bind(&Client::NotifyFlushDone, client_));
-
   return true;
 }
 
@@ -2503,6 +2516,18 @@ void V4L2SliceVideoDecodeAccelerator::OutputSurface(
   DCHECK_NE(output_record.picture_id, -1);
   output_record.at_client = true;
 
+  // If the surface still has a sync object assigned, destroy it. This means
+  // we didn't use this buffer for decode and we did not need to wait on it
+  // before enqueuing the buffer to the device.
+  if (output_record.egl_sync != EGL_NO_SYNC_KHR) {
+    if (eglDestroySyncKHR(egl_display_, output_record.egl_sync) != EGL_TRUE) {
+      LOGF(ERROR) << "eglDestroySyncKHR failed!";
+      NOTIFY_ERROR(PLATFORM_FAILURE);
+      return;
+    }
+    output_record.egl_sync = EGL_NO_SYNC_KHR;
+  }
+
   // TODO(posciak): Use visible size from decoder here instead
   // (crbug.com/402760). Passing (0, 0) results in the client using the
   // visible size extracted from the container instead.