Make Position::BeforeNode() to take const Node& instead of Node*

third_party/WebKit/Source/core/editing/commands/ApplyBlockElementCommand.cpp

 /*
  * Copyright (C) 2006, 2008 Apple Inc. All rights reserved.
  * Copyright (C) 2010 Google 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
@@ skipping 133 matching lines @@
   if (IsAtUnsplittableElement(caret_position)) {
     HTMLElement* blockquote = CreateBlockElement();
     InsertNodeAt(blockquote, caret_position, editing_state);
     if (editing_state->IsAborted())
       return;
     HTMLBRElement* placeholder = HTMLBRElement::Create(GetDocument());
     AppendNode(placeholder, blockquote, editing_state);
     if (editing_state->IsAborted())
       return;
     SetEndingSelection(SelectionInDOMTree::Builder()
-                           .Collapse(Position::BeforeNode(placeholder))
+                           .Collapse(Position::BeforeNode(*placeholder))
                            .SetIsDirectional(EndingSelection().IsDirectional())
                            .Build());
     return;
   }
 
   HTMLElement* blockquote_for_next_indent = nullptr;
   VisiblePosition end_of_current_paragraph = EndOfParagraph(start_of_selection);
   const VisiblePosition& visible_end_of_last_paragraph =
       EndOfParagraph(end_of_selection);
   const Position& end_of_next_last_paragraph =
@@ skipping 246 matching lines @@
 }
 
 HTMLElement* ApplyBlockElementCommand::CreateBlockElement() const {
   HTMLElement* element = CreateHTMLElement(GetDocument(), tag_name_);
   if (inline_style_.length())
     element->setAttribute(styleAttr, inline_style_);
   return element;
 }
 
 }  // namespace blink