Switch custom XMLHttpRequest bindings over to new-style ExceptionState.

Source/bindings/v8/ExceptionState.cpp

 /*
  * 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 62 matching lines @@
         return;
     }
 
     m_exception.set(m_isolate, exception);
 }
 
 void ExceptionState::throwTypeError(const String& message)
 {
     ASSERT(m_isolate);
     m_code = TypeError;
-    setException(V8ThrowException::createTypeError(message, m_isolate));
+    String processedMessage = addExceptionContext(message);

[Mike West, 2013/11/29 11:28:12]

Nit: I'd drop the temporary string here. You can just inline it in the call to
createTypeError.

[sof, 2013/11/29 11:36:05]

Done.

+    setException(V8ThrowException::createTypeError(processedMessage, m_isolate));
 }
 
 void TrackExceptionState::throwDOMException(const ExceptionCode& ec, const String& message)
 {
     m_code = ec;
 }
 
 void TrackExceptionState::throwTypeError(const String&)
 {
     m_code = TypeError;
@@ skipping 19 matching lines @@
             processedMessage = ExceptionMessages::failedToGet(propertyName(), interfaceName(), message);
         else if (m_context == SetterContext)
             processedMessage = ExceptionMessages::failedToSet(propertyName(), interfaceName(), message);
     } else if (!propertyName() && interfaceName() && m_context == ConstructionContext) {
         processedMessage = ExceptionMessages::failedToConstruct(interfaceName(), message);
     }
     return processedMessage;
 }
 
 } // namespace WebCore