Fix RunAfterPendingVideoFrames before CreateVideoFrame

RunAfterPendingVideoFrames is used to make sure VideoFrameFactoryImpl
pipeline is ordered and the callback is run after all pending
CreateVideoFrame is done. For this purpose it RequestImage() with the
same ImageSpec as last request and waits for request to complete.

It is possible that RunAfterPendingVideoFrames is called before any
CreateVideoFrame calls and so ImageSpec isn't initialized yet. This CL
fixes this by skipping RequestImage() in this case, as there should be
no pending CreateVideoFrame.

Bug: 1099384
Change-Id: I669718a8c470c1f0360a79c47317252025fdedd8
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2302410Reviewed-by: Frank Liberato <liberato@chromium.org>
Commit-Queue: Vasiliy Telezhnikov <vasilyt@chromium.org>
Cr-Commit-Position: refs/heads/master@{#791252}

media/gpu/android/video_frame_factory_impl.cc

@@ -200,8 +200,21 @@ void VideoFrameFactoryImpl::CreateVideoFrame_OnFrameInfoReady(
   // nothing. But in this case call comes from RunAfterPendingVideoFrames and we
   // just want to ask for the same image spec as before to order callback after
   // all RequestImage, so skip updating image_spec_ in this case.
-  if (output_buffer_renderer)
+  if (output_buffer_renderer) {
     image_spec_.coded_size = frame_info.coded_size;
+  } else {
+    // It is possible that we come here from RunAfterPendingVideoFrames before
+    // CreateVideoFrame was called. In this case we don't have coded_size, but
+    // it also means that there was no `image_provider_->RequestImage` calls so
+    // we can just run callback instantly.
+    if (image_spec_.coded_size.IsEmpty()) {
+      std::move(image_ready_cb)
+          .Run(nullptr, FrameInfoHelper::FrameInfo(),
+               SharedImageVideoProvider::ImageRecord());
+      return;
+    }
+  }
+  DCHECK(!image_spec_.coded_size.IsEmpty());
 
   auto cb = base::BindOnce(std::move(image_ready_cb),
                            std::move(output_buffer_renderer), frame_info);