Use const ref for LocalFrame::LocalFrameRoot and FrameTree::Top

third_party/WebKit/Source/core/editing/FrameSelection.cpp

 /*
  * Copyright (C) 2004, 2008, 2009, 2010 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 1030 matching lines @@
 DEFINE_TRACE(FrameSelection) {
   visitor->Trace(frame_);
   visitor->Trace(layout_selection_);
   visitor->Trace(selection_editor_);
   visitor->Trace(frame_caret_);
   SynchronousMutationObserver::Trace(visitor);
 }
 
 void FrameSelection::ScheduleVisualUpdate() const {
   if (Page* page = frame_->GetPage())
-    page->Animator().ScheduleVisualUpdate(frame_->LocalFrameRoot());
+    page->Animator().ScheduleVisualUpdate(&frame_->LocalFrameRoot());
 }
 
 void FrameSelection::ScheduleVisualUpdateForPaintInvalidationIfNeeded() const {
   if (FrameView* frame_view = frame_->View())
     frame_view->ScheduleVisualUpdateForPaintInvalidationIfNeeded();
 }
 
 bool FrameSelection::SelectWordAroundPosition(const VisiblePosition& position) {
   static const EWordSide kWordSideList[2] = {kRightWordIfOnBoundary,
                                              kLeftWordIfOnBoundary};
@@ skipping 118 matching lines @@
 }
 
 void showTree(const blink::FrameSelection* sel) {
   if (sel)
     sel->ShowTreeForThis();
   else
     LOG(INFO) << "Cannot showTree for <null> FrameSelection.";
 }
 
 #endif