Make sure send one WebTouchEvent ack per ui::TouchEvent

content/browser/renderer_host/render_widget_host_view_aura.h

Index: content/browser/renderer_host/render_widget_host_view_aura.h
diff --git a/content/browser/renderer_host/render_widget_host_view_aura.h b/content/browser/renderer_host/render_widget_host_view_aura.h
index 69fe661283393fdb0315cda39e74758e57cc291c..ed61fb8e1bd07bb01fb0c3cf45a6897136c5a005 100644
--- a/content/browser/renderer_host/render_widget_host_view_aura.h
+++ b/content/browser/renderer_host/render_widget_host_view_aura.h
@@ -364,6 +364,11 @@ class CONTENT_EXPORT RenderWidgetHostViewAura
   }
   const ui::MotionEventAura& pointer_state() const { return pointer_state_; }
 
+  // Reset unchange touch point to StateStationary for touchmove and
+  // touchcancel.
+  void MarkUnchangedTouchPointsAsStationary(blink::WebTouchEvent* event,
+                                            int touch_id);
+
  private:
   FRIEND_TEST_ALL_PREFIXES(RenderWidgetHostViewAuraTest,
                            PopupRetainsCaptureAfterMouseRelease);