Prepare SyntheticPointerAction to handle touch actions for multiple fingers

content/renderer/render_widget.h

Index: content/renderer/render_widget.h
diff --git a/content/renderer/render_widget.h b/content/renderer/render_widget.h
index 5eecc23c2729d62504f4a4ed8ebf4fef2d0cd047..01ea29dc67d77ddd14ac2b5185715a5aa7203097 100644
--- a/content/renderer/render_widget.h
+++ b/content/renderer/render_widget.h
@@ -308,6 +308,9 @@ class CONTENT_EXPORT RenderWidget
       std::unique_ptr<SyntheticGestureParams> gesture_params,
       const SyntheticGestureCompletionCallback& callback);
 
+  void QueueSyntheticGesture(
+      std::unique_ptr<SyntheticGestureParams> gesture_params);
+
   // Deliveres |message| together with compositor state change updates. The
   // exact behavior depends on |policy|.
   // This mechanism is not a drop-in replacement for IPC: messages sent this way