chore: add ImageBackgroundPropType (#32099)

Summary:
Added FlowType definition for ImageBackground component Props

## Changelog

[General] [Changed] - Add ImageBackground component type definition
[General] [Fixed] - ImageBackground now respects `imageStyle` width and height

Pull Request resolved: #32099

Test Plan:
- [ ] flow check passes
- [ ] rn-tester app runs

Reviewed By: charlesbdudley

Differential Revision: D30597737

Pulled By: yungsters

fbshipit-source-id: 9699ee2bb727a1a8f30d6ffe3a2845c8a134e89d

Author: Naturalclar

Libraries/Image/ImageBackground.js

@@ -10,10 +10,12 @@
 
 'use strict';
 
-const Image = require('./Image');
-const React = require('react');
-const StyleSheet = require('../StyleSheet/StyleSheet');
-const View = require('../Components/View/View');
+import Image from './Image';
+import * as React from 'react';
+import StyleSheet from '../StyleSheet/StyleSheet';
+import flattenStyle from '../StyleSheet/flattenStyle';
+import View from '../Components/View/View';
+import type {ImageBackgroundProps} from './ImageProps';
 
 /**
  * Very simple drop-in replacement for <Image> which supports nesting views.
@@ -39,7 +41,7 @@ const View = require('../Components/View/View');
  * AppRegistry.registerComponent('DisplayAnImageBackground', () => DisplayAnImageBackground);
  * ```
  */
-class ImageBackground extends React.Component<$FlowFixMeProps> {
+class ImageBackground extends React.Component<ImageBackgroundProps> {
   setNativeProps(props: Object) {
     // Work-around flow
     const viewRef = this._viewRef;
@@ -56,7 +58,7 @@ class ImageBackground extends React.Component<$FlowFixMeProps> {
 
   render(): React.Node {
     const {children, style, imageStyle, imageRef, ...props} = this.props;
-
+    const flattenedStyle = flattenStyle(style);
     return (
       <View
         accessibilityIgnoresInvertColors={true}
@@ -74,8 +76,8 @@ class ImageBackground extends React.Component<$FlowFixMeProps> {
               // So, we have to proxy/reapply these styles explicitly for actual <Image> component.
               // This workaround should be removed after implementing proper support of
               // intrinsic content size of the <Image>.
-              width: style?.width,
-              height: style?.height,
+              width: flattenedStyle?.width,
+              height: flattenedStyle?.height,
             },
             imageStyle,
           ]}

Libraries/Image/ImageProps.js

@@ -15,6 +15,8 @@ import type {EdgeInsetsProp} from '../StyleSheet/EdgeInsetsPropType';
 import type {ImageSource} from './ImageSource';
 import type {ViewStyleProp, ImageStyleProp} from '../StyleSheet/StyleSheet';
 import type {ViewProps} from '../Components/View/ViewPropTypes';
+import type {Node, Ref} from 'react';
+import typeof Image from './Image';
 
 export type ImageLoadEvent = SyntheticEvent<
   $ReadOnly<{|
@@ -171,3 +173,29 @@ export type ImageProps = {|
   src?: empty,
   children?: empty,
 |};
+
+export type ImageBackgroundProps = $ReadOnly<{|
+  ...ImageProps,
+  children?: Node,
+
+  /**
+   * Style applied to the outer View component
+   *
+   * See https://reactnative.dev/docs/imagebackground#style
+   */
+  style?: ?ViewStyleProp,
+
+  /**
+   * Style applied to the inner Image component
+   *
+   * See https://reactnative.dev/docs/imagebackground#imagestyle
+   */
+  imageStyle?: ?ImageStyleProp,
+
+  /**
+   * Allows to set a reference to the inner Image component
+   *
+   * See https://reactnative.dev/docs/imagebackground#imageref
+   */
+  imageRef?: Ref<Image>,
+|}>;