lib/Ext/field/DatePicker.js
function(picker, value) {
        var me = this,
            oldValue = me.getValue();

        me.setValue(value);
        me.fireEvent('select', me, value);
        me.onChange(me, value, oldValue);
    }
function(picker, value) {
        var me = this,
            oldValue = me.getValue();

        me.setValue(value);
        me.fireEvent('select', me, value);
        me.onChange(me, value, oldValue);
    }
Called when the picker changes its value.
@param {Ext.picker.Date} picker The date picker.
@param {Object} value The new value from the date picker.
@private