Fixed <rdar://problem/3980389> JavaScript bindings access incorrect runtime object

	Fixed <rdar://problem/3980389> JavaScript bindings access incorrect runtime object

	Only use special 'back door' property to get the runtime object if thisObj isn't
	already a runtime object.

	<gratuitous> Cleaned up a couple of strcmp on ClassInfo name.  Used == on
	ClassInfo pointer instead.

        Reviewed by Chris.

        * bindings/c/c_utility.cpp:
        (convertValueToNPVariant):
        * bindings/objc/WebScriptObject.mm:
        (+[WebScriptObject _convertValueToObjcValue:KJS::originExecutionContext:Bindings::executionContext:Bindings::]):
        * bindings/runtime_method.cpp:
        (RuntimeMethodImp::call):

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@8474 268f45cc-cd09-0410-ab3c-d52691b4dbfc