Track currentOwner for Fiber locally inside the reconciler

This means that usage internal to the reconciler can refer to it directly
without going through the dispatcher.

packages/react-dom/src/client/ReactDOMRootFB.js

@@ -61,7 +61,7 @@ import {LegacyRoot} from 'react-reconciler/src/ReactRootTags';
 import getComponentNameFromType from 'shared/getComponentNameFromType';
 import {has as hasInstance} from 'shared/ReactInstanceMap';
 
-import ReactSharedInternals from 'shared/ReactSharedInternals';
+import {currentOwner} from 'react-reconciler/src/ReactFiberAsyncDispatcher';
 
 import assign from 'shared/assign';
 
@@ -342,7 +342,7 @@ export function findDOMNode(
   componentOrElement: Element | ?React$Component<any, any>,
 ): null | Element | Text {
   if (__DEV__) {
-    const owner = (ReactSharedInternals.owner: any);
+    const owner = currentOwner;
     if (owner !== null && owner.stateNode !== null) {
       const warnedAboutRefsInRender = owner.stateNode._warnedAboutRefsInRender;
       if (!warnedAboutRefsInRender) {

packages/react-native-renderer/src/ReactNativePublicCompat.js

@@ -24,14 +24,14 @@ import {
   findHostInstanceWithWarning,
 } from 'react-reconciler/src/ReactFiberReconciler';
 import {doesFiberContain} from 'react-reconciler/src/ReactFiberTreeReflection';
-import ReactSharedInternals from 'shared/ReactSharedInternals';
 import getComponentNameFromType from 'shared/getComponentNameFromType';
+import {currentOwner} from 'react-reconciler/src/ReactFiberAsyncDispatcher';
 
 export function findHostInstance_DEPRECATED<TElementType: ElementType>(
   componentOrHandle: ?(ElementRef<TElementType> | number),
 ): ?ElementRef<HostComponent<mixed>> {
   if (__DEV__) {
-    const owner = ReactSharedInternals.owner;
+    const owner = currentOwner;
     if (owner !== null && owner.stateNode !== null) {
       if (!owner.stateNode._warnedAboutRefsInRender) {
         console.error(
@@ -86,7 +86,7 @@ export function findHostInstance_DEPRECATED<TElementType: ElementType>(
 
 export function findNodeHandle(componentOrHandle: any): ?number {
   if (__DEV__) {
-    const owner = ReactSharedInternals.owner;
+    const owner = currentOwner;
     if (owner !== null && owner.stateNode !== null) {
       if (!owner.stateNode._warnedAboutRefsInRender) {
         console.error(

packages/react-reconciler/src/ReactFiberAsyncDispatcher.js

@@ -29,13 +29,18 @@ function getCacheForType<T>(resourceType: () => T): T {
   return cacheForType;
 }
 
+export let currentOwner: Fiber | null = null;
+
 export const DefaultAsyncDispatcher: AsyncDispatcher = ({
   getCacheForType,
 }: any);
 
 if (__DEV__ || !disableStringRefs) {
   DefaultAsyncDispatcher.getOwner = (): null | Fiber => {
-    // TODO
-    return null;
+    return currentOwner;
   };
 }
+
+export function setCurrentOwner(fiber: null | Fiber) {
+  currentOwner = fiber;
+}

packages/react-reconciler/src/ReactFiberBeginWork.js

@@ -91,7 +91,6 @@ import {
   Passive,
   DidDefer,
 } from './ReactFiberFlags';
-import ReactSharedInternals from 'shared/ReactSharedInternals';
 import {
   debugRenderPhaseSideEffectsForStrictMode,
   disableLegacyContext,
@@ -297,6 +296,7 @@ import {
   pushRootMarkerInstance,
   TransitionTracingMarker,
 } from './ReactFiberTracingMarkerComponent';
+import {setCurrentOwner} from './ReactFiberAsyncDispatcher';
 
 // A special exception that's used to unwind the stack when an update flows
 // into a dehydrated boundary.
@@ -432,7 +432,7 @@ function updateForwardRef(
     markComponentRenderStarted(workInProgress);
   }
   if (__DEV__) {
-    ReactSharedInternals.owner = workInProgress;
+    setCurrentOwner(workInProgress);
     setIsRendering(true);
     nextChildren = renderWithHooks(
       current,
@@ -1150,7 +1150,7 @@ function updateFunctionComponent(
     markComponentRenderStarted(workInProgress);
   }
   if (__DEV__) {
-    ReactSharedInternals.owner = workInProgress;
+    setCurrentOwner(workInProgress);
     setIsRendering(true);
     nextChildren = renderWithHooks(
       current,
@@ -1373,7 +1373,7 @@ function finishClassComponent(
 
   // Rerender
   if (__DEV__ || !disableStringRefs) {
-    ReactSharedInternals.owner = workInProgress;
+    setCurrentOwner(workInProgress);
   }
   let nextChildren;
   if (
@@ -3419,7 +3419,7 @@ function updateContextConsumer(
   }
   let newChildren;
   if (__DEV__) {
-    ReactSharedInternals.owner = workInProgress;
+    setCurrentOwner(workInProgress);
     setIsRendering(true);
     newChildren = render(newValue);
     setIsRendering(false);

packages/react-reconciler/src/ReactFiberTreeReflection.js

@@ -12,7 +12,6 @@ import type {Container, SuspenseInstance} from './ReactFiberConfig';
 import type {SuspenseState} from './ReactFiberSuspenseComponent';
 
 import {get as getInstance} from 'shared/ReactInstanceMap';
-import ReactSharedInternals from 'shared/ReactSharedInternals';
 import getComponentNameFromFiber from 'react-reconciler/src/getComponentNameFromFiber';
 import {
   ClassComponent,
@@ -25,6 +24,7 @@ import {
   SuspenseComponent,
 } from './ReactWorkTags';
 import {NoFlags, Placement, Hydrating} from './ReactFiberFlags';
+import {currentOwner} from './ReactFiberAsyncDispatcher';
 
 export function getNearestMountedFiber(fiber: Fiber): null | Fiber {
   let node = fiber;
@@ -89,7 +89,7 @@ export function isFiberMounted(fiber: Fiber): boolean {
 
 export function isMounted(component: React$Component<any, any>): boolean {
   if (__DEV__) {
-    const owner = (ReactSharedInternals.owner: any);
+    const owner = currentOwner;
     if (owner !== null && owner.tag === ClassComponent) {
       const ownerFiber: Fiber = owner;
       const instance = ownerFiber.stateNode;

packages/react-reconciler/src/ReactFiberWorkLoop.js

@@ -203,7 +203,10 @@ import {
   resetHooksOnUnwind,
   ContextOnlyDispatcher,
 } from './ReactFiberHooks';
-import {DefaultAsyncDispatcher} from './ReactFiberAsyncDispatcher';
+import {
+  DefaultAsyncDispatcher,
+  setCurrentOwner,
+} from './ReactFiberAsyncDispatcher';
 import {
   createCapturedValueAtFiber,
   type CapturedValue,
@@ -1684,7 +1687,7 @@ function handleThrow(root: FiberRoot, thrownValue: any): void {
   resetHooksAfterThrow();
   resetCurrentDebugFiberInDEV();
   if (__DEV__ || !disableStringRefs) {
-    ReactSharedInternals.owner = null;
+    setCurrentOwner(null);
   }
 
   if (thrownValue === SuspenseException) {
@@ -2386,7 +2389,7 @@ function performUnitOfWork(unitOfWork: Fiber): void {
   }
 
   if (__DEV__ || !disableStringRefs) {
-    ReactSharedInternals.owner = null;
+    setCurrentOwner(null);
   }
 }
 
@@ -2501,7 +2504,7 @@ function replaySuspendedUnitOfWork(unitOfWork: Fiber): void {
   }
 
   if (__DEV__ || !disableStringRefs) {
-    ReactSharedInternals.owner = null;
+    setCurrentOwner(null);
   }
 }
 
@@ -2894,7 +2897,7 @@ function commitRootImpl(
 
     // Reset this to null before calling lifecycles
     if (__DEV__ || !disableStringRefs) {
-      ReactSharedInternals.owner = null;
+      setCurrentOwner(null);
     }
 
     // The commit phase is broken into several sub-phases. We do a separate pass