Reland "Send FrameSwapMessageQueue's messages in QueueMessageSwapPromise" with fixes

content/browser/renderer_host/render_widget_host_impl.h

Index: content/browser/renderer_host/render_widget_host_impl.h
diff --git a/content/browser/renderer_host/render_widget_host_impl.h b/content/browser/renderer_host/render_widget_host_impl.h
index 1b7738657333e8cb4a79ef20124bc55c8879791c..dd6b845d406965a4eecaa54d2f1582d6aa7d057a 100644
--- a/content/browser/renderer_host/render_widget_host_impl.h
+++ b/content/browser/renderer_host/render_widget_host_impl.h
@@ -593,6 +593,10 @@ class CONTENT_EXPORT RenderWidgetHostImpl
                              cc::CompositorFrame frame) override;
   void DidNotProduceFrame(const cc::BeginFrameAck& ack) override;
 
+  // Signals that a frame with token |frame_token| was finished processing. If
+  // there are any queued messages belonging to it, they will be processed.
+  void DidProcessFrame(uint32_t frame_token);
+
  protected:
   // ---------------------------------------------------------------------------
   // The following method is overridden by RenderViewHost to send upwards to
@@ -754,10 +758,6 @@ class CONTENT_EXPORT RenderWidgetHostImpl
   // Used for UMA logging how long the renderer was unresponsive.
   void LogHangMonitorUnresponsive();
 
-  // Signals that a frame with token |frame_token| was finished processing. If
-  // there are any queued messages belonging to it, they will be processed.
-  void DidProcessFrame(uint32_t frame_token);
-
   // Once both the frame and its swap messages arrive, we call this method to
   // process the messages. Virtual for tests.
   virtual void ProcessSwapMessages(std::vector<IPC::Message> messages);