Deprecate the Element.prefix setter

Source/core/frame/UseCounter.cpp

 
 /*
  * Copyright (C) 2012 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 712 matching lines @@
     case DocumentImportNodeOptionalArgument:
         return "The behavior of importNode() with no boolean argument is about to change from doing a deep clone to doing a shallow clone.  "
             "Make sure to pass an explicit boolean argument to keep your current behavior.";
 
     case OverflowChangedEvent:
         return "The 'overflowchanged' event is deprecated and may be removed. Please do not use it.";
 
     case HTMLHeadElementProfile:
         return "'HTMLHeadElement.profile' is deprecated. The reflected attribute has no effect.";
 
+    case ElementSetPrefix:
+        return "Setting 'Element.prefix' is deprecated, as it is read-only per DOM (http://dom.spec.whatwg.org/#element).";
+
     // Features that aren't deprecated don't have a deprecation message.
     default:
         return String();
     }
 }
 
 void UseCounter::count(CSSParserContext context, CSSPropertyID feature)
 {
     ASSERT(feature >= firstCSSProperty);
     ASSERT(feature <= lastCSSProperty);
@@ skipping 28 matching lines @@
 UseCounter* UseCounter::getFrom(const StyleSheetContents* sheetContents)
 {
     // FIXME: We may want to handle stylesheets that have multiple owners
     //        http://crbug.com/242125
     if (sheetContents && sheetContents->hasSingleOwnerNode())
         return getFrom(sheetContents->singleOwnerDocument());
     return 0;
 }
 
 } // namespace WebCore