Replaced PassRefPtr copies with moves in Source/core.

third_party/WebKit/Source/core/layout/api/LayoutItem.h

 // Copyright 2016 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 LayoutItem_h
 #define LayoutItem_h
 
 #include "core/inspector/InspectorTraceEvents.h"
 #include "core/layout/LayoutObject.h"
 
@@ skipping 174 matching lines @@
         return m_layoutObject->mutableStyle();
     }
 
     ComputedStyle& mutableStyleRef() const
     {
         return m_layoutObject->mutableStyleRef();
     }
 
     void setStyle(PassRefPtr<ComputedStyle> style)
     {
-        m_layoutObject->setStyle(style);
+        m_layoutObject->setStyle(std::move(style));
     }
 
     LayoutSize offsetFromContainer(const LayoutItem& item) const
     {
         return m_layoutObject->offsetFromContainer(item.layoutObject());
     }
 
     LayoutViewItem view() const;
 
     FrameView* frameView() const
@@ skipping 107 matching lines @@
 
 private:
     LayoutObject* m_layoutObject;
 
     friend class LayoutAPIShim;
 };
 
 } // namespace blink
 
 #endif // LayoutItem_h