Popover doesn't show content on iPad

`UITextFieldWithPicker` and `UITextFieldWithDatePicker`

![ios 7 0 3 11b508 2013-12-10 12-14-25](https://f.cloud.github.com/assets/19714/1711259/2d3a0e96-6149-11e3-86f2-33d3a618dd13.jpg)