facebook#22990 add RCTDatePickerNativeComponent types (facebook#23013)

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Changelog:
----------

[iOS] [Changed] - As mentioned in facebook#22990, I have moved native components required by DatePickerIOS.ios.js into separate files and added Flow Typing.
Pull Request resolved: facebook#23013

Differential Revision: D13697591

Pulled By: TheSavior

fbshipit-source-id: 5aec5a2270cbfc708f3e3a67662abd8071f1333f

Libraries/Components/DatePicker/DatePickerIOS.ios.js

@@ -18,12 +18,11 @@ const StyleSheet = require('StyleSheet');
 const View = require('View');
 
 const invariant = require('invariant');
-const requireNativeComponent = require('requireNativeComponent');
 
 import type {ViewProps} from 'ViewPropTypes';
 import type {SyntheticEvent} from 'CoreEventTypes';
 
-const RCTDatePickerIOS = requireNativeComponent('RCTDatePicker');
+const RCTDatePickerNativeComponent = require('RCTDatePickerNativeComponent');
 
 type Event = SyntheticEvent<
   $ReadOnly<{|
@@ -119,7 +118,7 @@ class DatePickerIOS extends React.Component<Props> {
   };
 
   // $FlowFixMe How to type a native component to be able to call setNativeProps
-  _picker: ?React.ElementRef<typeof RCTDatePickerIOS> = null;
+  _picker: ?React.ElementRef<typeof RCTDatePickerNativeComponent> = null;
 
   componentDidUpdate() {
     if (this.props.date) {
@@ -147,7 +146,7 @@ class DatePickerIOS extends React.Component<Props> {
     );
     return (
       <View style={props.style}>
-        <RCTDatePickerIOS
+        <RCTDatePickerNativeComponent
           testID={props.testID}
           ref={picker => {
             this._picker = picker;

Libraries/Components/DatePicker/RCTDatePickerNativeComponent.js

@@ -0,0 +1,41 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @format
+ * @flow
+ */
+
+'use strict';
+
+const requireNativeComponent = require('requireNativeComponent');
+
+import type {SyntheticEvent} from 'CoreEventTypes';
+import type {ViewProps} from 'ViewPropTypes';
+import type {NativeComponent} from 'ReactNative';
+
+type Event = SyntheticEvent<
+  $ReadOnly<{|
+    timestamp: number,
+  |}>,
+>;
+
+type NativeProps = $ReadOnly<{|
+  ...ViewProps,
+  date?: ?number,
+  initialDate?: ?Date,
+  locale?: ?string,
+  maximumDate?: ?number,
+  minimumDate?: ?number,
+  minuteInterval?: ?(1 | 2 | 3 | 4 | 5 | 6 | 10 | 12 | 15 | 20 | 30),
+  mode?: ?('date' | 'time' | 'datetime'),
+  onChange?: ?(event: Event) => void,
+  timeZoneOffsetInMinutes?: ?number,
+|}>;
+type RCTDatePickerNativeType = Class<NativeComponent<NativeProps>>;
+
+module.exports = ((requireNativeComponent(
+  'RCTDatePicker',
+): any): RCTDatePickerNativeType);