[TIMOB-16046] iOS7: keyboardToolbar disappears after focussing textField 2-3 times

var win = Ti.UI.createWindow({
	backgroundColor : 'white'
});

var fixedSpace = Ti.UI.createButton({
	systemButton : Ti.UI.iPhone.SystemButton.FIXED_SPACE,
	width : 213
});
var doneButton = Ti.UI.createButton({
	right : 10,
	width : 85,
	height : 30,
	backgroundImage : 'global-btn-up.9.png',
	color : 'Black',
	font : {
		fontSize : 14,
		fontFamily : 'Helvetica Neue',
		fontWeight : 'Bold',
	}
});
doneButton.addEventListener('click', function(e) {
	textField.blur();
});
var textField = Titanium.UI.createTextField({
	borderStyle : Titanium.UI.INPUT_BORDERSTYLE_BEZEL,
	hintText : 'Focus to see keyboard with toolbar',
	keyboardToolbar : [fixedSpace, doneButton],
	keyboardType : Ti.UI.KEYBOARD_NUMBER_PAD,
	keyboardToolbarColor : '#999',
	keyboardToolbarHeight : 40,
	top : 10,
	width : 300,
	height : 35
});

win.add(textField);
win.open();