Ensure RemoteViewportIntersection rect persists across frame navigations

content/browser/renderer_host/render_widget_host_view_base.h

Index: content/browser/renderer_host/render_widget_host_view_base.h
diff --git a/content/browser/renderer_host/render_widget_host_view_base.h b/content/browser/renderer_host/render_widget_host_view_base.h
index 1f1a6b919a3e29df619bfcc1974f485021d861da..3f7581af948f71120754a1ffff68a56c29f879e0 100644
--- a/content/browser/renderer_host/render_widget_host_view_base.h
+++ b/content/browser/renderer_host/render_widget_host_view_base.h
@@ -317,6 +317,10 @@ class CONTENT_EXPORT RenderWidgetHostViewBase : public RenderWidgetHostView,
   // need to also be resolved.
   virtual bool IsRenderWidgetHostViewChildFrame();
 
+  // Notify the View that a screen rect update is being sent to the
+  // RenderWidget. Related platform-specific updates can be sent from here.
+  virtual void WillSendScreenRects() {}
+
   // Returns true if the current view is in virtual reality mode.
   virtual bool IsInVR() const;