fix(android): improve Window focus/blur events

[m1ga]

Will fire blur/focus event when you drag down the statusbar on your phone.

Note: This will also fire when an alert is shown! That is currently not the case. So I'm not sure if we should use a different event for this as it may cause problems in existing apps.

var win = Ti.UI.createWindow({});
var btn = Ti.UI.createButton({
	title: "alert",
})

win.add(btn);
win.open();

win.addEventListener("focus", function(){
	console.log("win focus")
})
win.addEventListener("blur", function(){
	console.log("win blur")
})

btn.addEventListener("click", function(e) {
	alert(1);
})

I could change it to windowblur and windowfocus so you have a different event for these new blur/focus and it won't break any exisint blur/focus usage on a window