Manipulate the child browser window
BrowserWindowProxy object is returned from
window.open and provides limited functionality with the child window.
BrowserWindowProxy object has the following instance methods:
Removes focus from the child window.
Forcefully closes the child window without calling its unload event.
Evaluates the code in the child window.
Focuses the child window (brings the window to front).
Invokes the print dialog on the child window.
Sends a message to the child window with the specified origin or
* for no origin preference.
In addition to these methods, the child window implements
window.opener object with no properties and a single method.
BrowserWindowProxy object has the following instance properties:
Boolean that is set to true after the child window gets closed.