Mark the AtomicString(const String&) constructor as explicit

Source/core/rendering/ClipPathOperation.h

 /*
  * Copyright (C) 2012 Adobe Systems Incorporated. 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.
@@ skipping 47 matching lines @@
     ClipPathOperation(OperationType type)
         : m_type(type)
     {
     }
 
     OperationType m_type;
 };
 
 class ReferenceClipPathOperation : public ClipPathOperation {
 public:
-    static PassRefPtr<ReferenceClipPathOperation> create(const String& url, const String& fragment)
+    static PassRefPtr<ReferenceClipPathOperation> create(const String& url, const AtomicString& fragment)
     {
         return adoptRef(new ReferenceClipPathOperation(url, fragment));
     }
 
     const String& url() const { return m_url; }
-    const String& fragment() const { return m_fragment; }
+    const AtomicString& fragment() const { return m_fragment; }
 
 private:
     virtual bool operator==(const ClipPathOperation& o) const OVERRIDE
     {
         return isSameType(o) && m_url == static_cast<const ReferenceClipPathOperation&>(o).m_url;
     }
 
-    ReferenceClipPathOperation(const String& url, const String& fragment)
+    ReferenceClipPathOperation(const String& url, const AtomicString& fragment)
         : ClipPathOperation(REFERENCE)
         , m_url(url)
         , m_fragment(fragment)
     {
     }
 
     String m_url;
-    String m_fragment;
+    AtomicString m_fragment;
 };
 
 DEFINE_TYPE_CASTS(ReferenceClipPathOperation, ClipPathOperation, op, op->type() == ClipPathOperation::REFERENCE, op.type() == ClipPathOperation::REFERENCE);
 
 class ShapeClipPathOperation : public ClipPathOperation {
 public:
     static PassRefPtr<ShapeClipPathOperation> create(PassRefPtr<BasicShape> shape)
     {
         return adoptRef(new ShapeClipPathOperation(shape));
     }
@@ skipping 25 matching lines @@
 DEFINE_TYPE_CASTS(ShapeClipPathOperation, ClipPathOperation, op, op->type() == ClipPathOperation::SHAPE, op.type() == ClipPathOperation::SHAPE);
 
 inline bool ShapeClipPathOperation::operator==(const ClipPathOperation& o) const
 {
     return isSameType(o) && *m_shape == *toShapeClipPathOperation(o).m_shape;
 }
 
 }
 
 #endif // ClipPathOperation_h