Fix declare_types! doc string for grab closes
@@ -219,7 +219,7 @@ macro_rules! impl_managed {
/// method hello(call) {
/// let scope = call.scope;
/// let name = try!(try!(call.arguments.require(scope, 0)).to_string(scope)).value();
-/// let msg = vm::lock(call.arguments.this(scope), |greeter| {
+/// let msg = call.arguments.this(call.scope).grab(|x| {
/// format!("{}, {}!", greeter.greeting, name)
/// });
/// Ok(try!(JsString::new_or_throw(scope, &msg[..])).upcast())
