Native propTypes RCTDatePickerIOS !== propTypes DatePickerIOS

Summary:
The propTypes of RCTDatePickerIOS do not fit with the propTypes of DatePickerIOS.
All dates (date, minimumDate, maximumDate) are a timestamp (check line 126), so they should have propType number.
OnDateChange function should not be required since it is called onChange in the iOS implementation.

The problem currently causes warnings that the given types are wrong, while they were added correctly.
Closes https://github.com/facebook/react-native/pull/7833

Differential Revision: D3371324

Pulled By: nicklockwood

fbshipit-source-id: bca5b2bbe7e9dd2e045288bfbd268578848c7bff

Libraries/Components/DatePicker/DatePickerIOS.ios.js

@@ -145,8 +145,15 @@ const styles = StyleSheet.create({
   },
 });
 
-var RCTDatePickerIOS = requireNativeComponent('RCTDatePicker', DatePickerIOS, {
-  nativeOnly: { onChange: true },
+const RCTDatePickerIOS = requireNativeComponent('RCTDatePicker', {
+  propTypes: {
+    ...DatePickerIOS.propTypes,
+    date: PropTypes.number,
+    minimumDate: PropTypes.number,
+    maximumDate: PropTypes.number,
+    onDateChange: () => null,
+    onChange: PropTypes.func,
+  }
 });
 
 module.exports = DatePickerIOS;