Rewrite references to "wtf/" to "platform/wtf/" in core/layout.

third_party/WebKit/Source/core/layout/ng/ng_column_layout_algorithm.h

 // Copyright 2017 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef NGColumnLayoutAlgorithm_h
 #define NGColumnLayoutAlgorithm_h
 
 #include "core/layout/ng/ng_block_layout_algorithm.h"
 #include "core/layout/ng/ng_break_token.h"
 #include "core/layout/ng/ng_constraint_space.h"
 #include "core/layout/ng/ng_layout_result.h"
-#include "wtf/RefPtr.h"
+#include "platform/wtf/RefPtr.h"
 
 namespace blink {
 
 class NGBlockNode;
 
 class CORE_EXPORT NGColumnLayoutAlgorithm : public NGBlockLayoutAlgorithm {
  public:
   NGColumnLayoutAlgorithm(NGBlockNode* node,
                           NGConstraintSpace* space,
                           NGBreakToken* break_token = nullptr);
 
   RefPtr<NGLayoutResult> Layout() override;
 };
 
 }  // namespace Blink
 
 #endif  // NGColumnLayoutAlgorithm_h