rem: return this._findProxyForURL(testURI, testHost); 
add: return this._findProxyForURL.call(this._sandBox, testURI, testHost); 
context:     getProxyForURI: function(testURI, testHost) {        if (!this._findProxyForURL)            return null;        // Call the original function        return this._findProxyForURL(testURI, testHost);    }
meta: 9421	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/9421/df9bd64f879de67f2678fdb63070c6a8d420250d/nsProxyAutoConfig.js/buggy/netwerk/base/src/nsProxyAutoConfig.js