The Tor Browser / file revision

 // Check Debugger.Object.prototype.unwrap surfaces.

 load(libdir + 'asserts.js');

 var dbg = new Debugger();

 var g = newGlobal();

 var gw = dbg.addDebuggee(g);

 assertEq(Object.getOwnPropertyDescriptor(gw, 'unwrap'), undefined);

 var d = Object.getOwnPropertyDescriptor(Object.getPrototypeOf(gw), 'unwrap');

 assertEq(d.enumerable, false);

 assertEq(d.configurable, true);

 assertEq(d.writable, true);

 assertEq(typeof gw.unwrap, "function");

 assertEq(gw.unwrap.length, 0);

 assertEq(gw.unwrap.name, "unwrap");

 // It can be called.

 gw.unwrap();

 // You shouldn't be able to apply the accessor to the prototype.

 assertThrowsInstanceOf(function () { Debugger.Object.prototype.unwrap(); }, TypeError);