Add ability to override the ViewStyle of the root View component (#44665)

Summary:
In order to host a ReactNative surface whose size is controlled by the RN content rather than the size of the surface, we need the ability to remove  the flex:1 style on the root View component.

`SurfaceHandler` has layout functions which take a `LayoutConstraint` (so min/max size).   The root View component in `AppContainer` has a hardcoded `flex:1` style.  This view is above the `WrapperComponent`, which we can currently override.  But I dont see anyway to avoid the root View having that flex style.  This flex style means that the rootview will always be the maxheight passed into the layout functions on `SurfaceHandler`.  Which prevents allowing RN surfaces that can size themselves based on their content.

This change adds a `setRootViewStyleProvider` method to `AppRegistry`, which works similar to `setWrapperComponentProvider` but allows apps to override the style property on the root View component.  In particular, this allows apps to remove the flex:1 style, which is required to enable react surfaces which are sized based on their contents.

## Changelog:

Pick one each for the category and type tags:

[GENERAL] [ADDED] - Added AppRegistry.setRootViewStyleProvider

Pull Request resolved: https://github.com/facebook/react-native/pull/44665

Test Plan: Will be including this change into react-native-windows to enable scenarios with content sized surfaces within Microsoft Office to work with the new architecture.  Would like signoff on this direction before I go and integrate it there.

Reviewed By: javache

Differential Revision: D58138443

Pulled By: hoxyq

fbshipit-source-id: 95ab4842aa7f827867788d8787527f9675cf4fcc

packages/react-native/Libraries/ReactNative/AppContainer-dev.js

@@ -92,6 +92,7 @@ const AppContainer = ({
   rootTag,
   showArchitectureIndicator,
   WrapperComponent,
+  rootViewStyle,
 }: Props): React.Node => {
   const appContainerRootViewRef: AppContainerRootViewRef = React.useRef(null);
   const innerViewRef: InspectedViewRef = React.useRef(null);
@@ -141,7 +142,7 @@ const AppContainer = ({
       collapsable={reactDevToolsAgent == null && !shouldRenderInspector}
       pointerEvents="box-none"
       key={key}
-      style={styles.container}
+      style={rootViewStyle || styles.container}
       ref={innerViewRef}>
       {children}
     </View>
@@ -167,7 +168,7 @@ const AppContainer = ({
     <RootTagContext.Provider value={createRootTag(rootTag)}>
       <View
         ref={appContainerRootViewRef}
-        style={styles.container}
+        style={rootViewStyle || styles.container}
         pointerEvents="box-none">
         {innerView}
 

packages/react-native/Libraries/ReactNative/AppContainer-prod.js

@@ -23,6 +23,7 @@ const AppContainer = ({
   rootTag,
   showArchitectureIndicator,
   WrapperComponent,
+  rootViewStyle,
 }: Props): React.Node => {
   let innerView = children;
 
@@ -39,7 +40,7 @@ const AppContainer = ({
 
   return (
     <RootTagContext.Provider value={createRootTag(rootTag)}>
-      <View style={styles.root} pointerEvents="box-none">
+      <View style={rootViewStyle || styles.root} pointerEvents="box-none">
         {innerView}
       </View>
     </RootTagContext.Provider>

packages/react-native/Libraries/ReactNative/AppContainer.js

@@ -8,6 +8,7 @@
  * @flow
  */
 
+import type {ViewStyleProp} from '../StyleSheet/StyleSheet';
 import type {RootTag} from './RootTag';
 
 import * as React from 'react';
@@ -19,6 +20,7 @@ export type Props = $ReadOnly<{|
   initialProps?: {...},
   showArchitectureIndicator?: boolean,
   WrapperComponent?: ?React.ComponentType<any>,
+  rootViewStyle?: ?ViewStyleProp,
   internal_excludeLogBox?: boolean,
   internal_excludeInspector?: boolean,
 |}>;

packages/react-native/Libraries/ReactNative/AppRegistry.d.ts

@@ -9,6 +9,7 @@
 
 import type * as React from 'react';
 import type {IPerformanceLogger} from '../Utilities/IPerformanceLogger';
+import type {ViewStyle} from '../StyleSheet/StyleSheetTypes';
 
 type Task = (taskData: any) => Promise<void>;
 type TaskProvider = () => Task;
@@ -34,6 +35,8 @@ export type WrapperComponentProvider = (
   appParameters: any,
 ) => React.ComponentType<any>;
 
+export type RootViewStyleProvider = (appParameters: any) => ViewStyle;
+
 /**
  * `AppRegistry` is the JS entry point to running all React Native apps.  App
  * root components should register themselves with
@@ -54,6 +57,10 @@ export namespace AppRegistry {
     provider: WrapperComponentProvider,
   ): void;
 
+  export function setRootViewStyleProvider(
+    provider: RootViewStyleProvider,
+  ): void;
+
   export function registerConfig(config: AppConfig[]): void;
 
   export function registerComponent(

packages/react-native/Libraries/ReactNative/AppRegistry.js

@@ -8,6 +8,7 @@
  * @format
  */
 
+import type {ViewStyleProp} from '../StyleSheet/StyleSheet';
 import type {RootTag} from '../Types/RootTagTypes';
 import type {IPerformanceLogger} from '../Utilities/createPerformanceLogger';
 import type {DisplayModeType} from './DisplayMode';
@@ -60,6 +61,7 @@ export type Registry = {
 export type WrapperComponentProvider = (
   appParameters: Object,
 ) => React$ComponentType<any>;
+export type RootViewStyleProvider = (appParameters: Object) => ViewStyleProp;
 
 const runnables: Runnables = {};
 let runCount = 1;
@@ -70,6 +72,7 @@ let componentProviderInstrumentationHook: ComponentProviderInstrumentationHook =
   (component: ComponentProvider) => component();
 
 let wrapperComponentProvider: ?WrapperComponentProvider;
+let rootViewStyleProvider: ?RootViewStyleProvider;
 let showArchitectureIndicator = false;
 
 /**
@@ -82,6 +85,10 @@ const AppRegistry = {
     wrapperComponentProvider = provider;
   },
 
+  setRootViewStyleProvider(provider: RootViewStyleProvider) {
+    rootViewStyleProvider = provider;
+  },
+
   enableArchitectureIndicator(enabled: boolean): void {
     showArchitectureIndicator = enabled;
   },
@@ -130,6 +137,7 @@ const AppRegistry = {
         appParameters.initialProps,
         appParameters.rootTag,
         wrapperComponentProvider && wrapperComponentProvider(appParameters),
+        rootViewStyleProvider && rootViewStyleProvider(appParameters),
         appParameters.fabric,
         showArchitectureIndicator,
         scopedPerformanceLogger,

packages/react-native/Libraries/ReactNative/renderApplication.js

@@ -8,6 +8,7 @@
  * @flow
  */
 
+import type {ViewStyleProp} from '../StyleSheet/StyleSheet';
 import type {IPerformanceLogger} from '../Utilities/createPerformanceLogger';
 
 import GlobalPerformanceLogger from '../Utilities/GlobalPerformanceLogger';
@@ -32,6 +33,7 @@ export default function renderApplication<Props: Object>(
   initialProps: Props,
   rootTag: any,
   WrapperComponent?: ?React.ComponentType<any>,
+  rootViewStyle?: ?ViewStyleProp,
   fabric?: boolean,
   showArchitectureIndicator?: boolean,
   scopedPerformanceLogger?: IPerformanceLogger,
@@ -52,6 +54,7 @@ export default function renderApplication<Props: Object>(
         fabric={fabric}
         showArchitectureIndicator={showArchitectureIndicator}
         WrapperComponent={WrapperComponent}
+        rootViewStyle={rootViewStyle}
         initialProps={initialProps ?? Object.freeze({})}
         internal_excludeLogBox={isLogBox}>
         <RootComponent {...initialProps} rootTag={rootTag} />

packages/react-native/Libraries/__tests__/__snapshots__/public-api-test.js.snap

@@ -6508,6 +6508,7 @@ exports[`public API should not change unintentionally Libraries/ReactNative/AppC
   initialProps?: { ... },
   showArchitectureIndicator?: boolean,
   WrapperComponent?: ?React.ComponentType<any>,
+  rootViewStyle?: ?ViewStyleProp,
   internal_excludeLogBox?: boolean,
   internal_excludeInspector?: boolean,
 |}>;
@@ -6573,8 +6574,10 @@ export type Registry = {
 export type WrapperComponentProvider = (
   appParameters: Object
 ) => React$ComponentType<any>;
+export type RootViewStyleProvider = (appParameters: Object) => ViewStyleProp;
 declare const AppRegistry: {
   setWrapperComponentProvider(provider: WrapperComponentProvider): void,
+  setRootViewStyleProvider(provider: RootViewStyleProvider): void,
   enableArchitectureIndicator(enabled: boolean): void,
   registerConfig(config: Array<AppConfig>): void,
   registerComponent(
@@ -6913,6 +6916,7 @@ exports[`public API should not change unintentionally Libraries/ReactNative/rend
   initialProps: Props,
   rootTag: any,
   WrapperComponent?: ?React.ComponentType<any>,
+  rootViewStyle?: ?ViewStyleProp,
   fabric?: boolean,
   showArchitectureIndicator?: boolean,
   scopedPerformanceLogger?: IPerformanceLogger,