Consolidate read-only exception throwing for SVG*TearOffs

third_party/WebKit/Source/core/svg/properties/SVGPropertyTearOff.h

 /*
  * Copyright (C) 2013 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 20 matching lines @@
 #ifndef SVGPropertyTearOff_h
 #define SVGPropertyTearOff_h
 
 #include "core/dom/QualifiedName.h"
 #include "core/svg/SVGElement.h"
 #include "core/svg/properties/SVGProperty.h"
 #include "platform/heap/Handle.h"
 
 namespace blink {
 
+class ExceptionState;
+
 enum PropertyIsAnimValType {
     PropertyIsNotAnimVal,
     PropertyIsAnimVal
 };
 
 class SVGPropertyTearOffBase : public GarbageCollectedFinalized<SVGPropertyTearOffBase> {
 public:
     virtual ~SVGPropertyTearOffBase() { }
 
     PropertyIsAnimValType propertyIsAnimVal() const
@@ skipping 41 matching lines @@
         m_contextElement = contextElement;
         m_attributeName = attributeName;
     }
 
     virtual AnimatedPropertyType type() const = 0;
 
     DEFINE_INLINE_VIRTUAL_TRACE()
     {
     }
 
+    static void throwReadOnly(ExceptionState&);
+
 protected:
     SVGPropertyTearOffBase(SVGElement* contextElement, PropertyIsAnimValType propertyIsAnimVal, const QualifiedName& attributeName = QualifiedName::null())
         : m_contextElement(contextElement)
         , m_propertyIsAnimVal(propertyIsAnimVal)
         , m_isReadOnlyProperty(false)
         , m_attributeName(attributeName)
     {
     }
 
 private:
@@ skipping 42 matching lines @@
         ASSERT(m_target);
     }
 
 private:
     Member<Property> m_target;
 };
 
 } // namespace blink
 
 #endif // SVGPropertyTearOff_h