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

content/common/gpu/media/fake_video_decode_accelerator.cc

Index: content/common/gpu/media/fake_video_decode_accelerator.cc
diff --git a/content/common/gpu/media/fake_video_decode_accelerator.cc b/content/common/gpu/media/fake_video_decode_accelerator.cc
index f8111623d0581a4f34191b0c73a4c9e3fc449731..f3fa5137ccedb0d529c92f47fa840abe3b260197 100644
--- a/content/common/gpu/media/fake_video_decode_accelerator.cc
+++ b/content/common/gpu/media/fake_video_decode_accelerator.cc
@@ -53,6 +53,14 @@ bool FakeVideoDecodeAccelerator::Initialize(const Config& config,
     return false;
   }
 
+  if (config.flush_mode != Config::FlushMode::KEEP_OUTPUT_BUFFERS &&
+      config.flush_mode != Config::FlushMode::RETURN_OUTPUT_BUFFERS) {
+    NOTIMPLEMENTED() << "Unsupported Config::FlushMode";
+    return false;
+  }
+
+  config_ = config;
+
   // V4L2VideoDecodeAccelerator waits until first decode call to ask for buffers
   // This class asks for it on initialization instead.
   client_ = client;
@@ -80,11 +88,9 @@ void FakeVideoDecodeAccelerator::Decode(
                             weak_this_factory_.GetWeakPtr()));
 }
 
-// Similar to UseOutputBitstreamBuffer for the encode accelerator.
 void FakeVideoDecodeAccelerator::AssignPictureBuffers(
     const std::vector<media::PictureBuffer>& buffers) {
-  DCHECK(buffers.size() == kNumBuffers);
-  DCHECK(!(buffers.size()%2));
+  DCHECK_GE(buffers.size(), kNumBuffers);
 
   // Save buffers and mark all buffers as ready for use.
   std::unique_ptr<uint8_t[]> white_data(
@@ -165,29 +171,38 @@ bool FakeVideoDecodeAccelerator::TryToSetupDecodeOnSeparateThread(
   return false;
 }
 
+void FakeVideoDecodeAccelerator::ReturnPicture(int32_t picture_buffer_id,
+                                               int32_t bitstream_buffer_id) {
+  const media::Picture picture =
+      media::Picture(picture_buffer_id, bitstream_buffer_id,
+                     gfx::Rect(frame_buffer_size_), false);
+
+  client_->PictureReady(picture);
+}
+
 void FakeVideoDecodeAccelerator::DoPictureReady() {
-  if (flushing_ && queued_bitstream_ids_.empty()) {
-    flushing_ = false;
-    client_->NotifyFlushDone();
-  }
   while (!free_output_buffers_.empty() && !queued_bitstream_ids_.empty()) {
     int bitstream_id = queued_bitstream_ids_.front();
     queued_bitstream_ids_.pop();
+
     int buffer_id = free_output_buffers_.front();
     free_output_buffers_.pop();
 
-    const media::Picture picture =
-        media::Picture(buffer_id,
-                       bitstream_id,
-                       gfx::Rect(frame_buffer_size_),
-                       false);
-    client_->PictureReady(picture);
-    // Bitstream no longer needed.
+    ReturnPicture(buffer_id, bitstream_id);
     client_->NotifyEndOfBitstreamBuffer(bitstream_id);
-    if (flushing_ && queued_bitstream_ids_.empty()) {
-      flushing_ = false;
-      client_->NotifyFlushDone();
+  }
+
+  if (flushing_ && queued_bitstream_ids_.empty()) {
+    if (config_.flush_mode == Config::FlushMode::RETURN_OUTPUT_BUFFERS) {
+      while (!free_output_buffers_.empty()) {
+        int32_t picture_buffer_id = free_output_buffers_.front();
+        free_output_buffers_.pop();
+        ReturnPicture(picture_buffer_id, -1);
+      }
     }
+
+    flushing_ = false;
+    client_->NotifyFlushDone();
   }
 }