Summary:
On conditional rendering if child is null then the PickerAndroid breaks.
when conditional rendering is used then picker breaks when the child is null.
This conditional rendering inside Picker fails when a is 1, because child will be null in PickerAndroid.android.js.
```
{
this.state.a === 2 && <Picker.Item label="value" value="value" />
}
```
[ANDROID] [FIXED] - Filter props.children.
Pull Request resolved: https://github.com/facebook/react-native/pull/23884
Differential Revision: D14436860
Pulled By: cpojer
fbshipit-source-id: 6a8fca604acf77c20729f26a53cd7f67e514deac
85e8b3e21d