Deliver IPC messages together with SwapCompositorFrame

content/renderer/message_delivery_policy.h

+// Copyright 2014 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.
+
+#ifndef CONTENT_RENDERER_MESSAGE_DELIVERY_POLICY_H_
+#define CONTENT_RENDERER_MESSAGE_DELIVERY_POLICY_H_
+
+namespace content {
+
+enum MessageDeliveryPolicy {
+  // If a commit was requested before the message was enqueued the message
+  // will be delivered with the swap corresponding to that commit. Otherwise
+  // the message will be sent immediately using regular IPC.
+  // If the commit is aborted or optimized out the message is sent using regular
+  // IPC.
+  MESSAGE_DELIVERY_POLICY_WITH_VISUAL_STATE,
+  // The message will be delivered with the next swap.
+  // If the swap is optimized out, the message is sent using regular IPC.
+  // If the swap fails the message remains enqueued.
+  MESSAGE_DELIVERY_POLICY_WITH_NEXT_SWAP,
+};
+
+}  // namespace content
+
+#endif  // CONTENT_RENDERER_MESSAGE_DELIVERY_POLICY_H_