It's not necessary to create HandleScope in v8 native binding functions,
because it's guarrenteed that the there is a upper HandleScope when the
native function is called. So unless we are urgent to free the handles,
not using HandleScope in native binding functions is a cleaner and safer
choice.
It's important to bind application menu items to curtain actions of
first responder, like 'quit', 'minimize', 'copy' etc. This API gives
developers ability to do most of them in javascript.
