Implement ActivityInstance in FiberConfigDOM (facebook#32842)

Stacked on facebook#32851 and facebook#32900.

This implements the equivalent Configs for ActivityInstance as we have
for SuspenseInstance. These can be implemented as comments but they
don't have to be and can be implemented differently in the renderer.

This seems like a lot duplication but it's actually ends mostly just
calling the same methods underneath and the wrappers compiles out.

This doesn't leave the Activity dehydrated yet. It just hydrates into it
immediately.

Author: sebmarkbage

packages/react-dom-bindings/src/client/ReactDOMComponentTree.js

@@ -17,6 +17,7 @@ import type {
   Container,
   TextInstance,
   Instance,
+  ActivityInstance,
   SuspenseInstance,
   Props,
   HoistableRoot,
@@ -30,9 +31,10 @@ import {
   HostText,
   HostRoot,
   SuspenseComponent,
+  ActivityComponent,
 } from 'react-reconciler/src/ReactWorkTags';
 
-import {getParentSuspenseInstance} from './ReactFiberConfigDOM';
+import {getParentHydrationBoundary} from './ReactFiberConfigDOM';
 
 import {enableScopeAPI} from 'shared/ReactFeatureFlags';
 
@@ -59,7 +61,12 @@ export function detachDeletedInstance(node: Instance): void {
 
 export function precacheFiberNode(
   hostInst: Fiber,
-  node: Instance | TextInstance | SuspenseInstance | ReactScopeInstance,
+  node:
+    | Instance
+    | TextInstance
+    | SuspenseInstance
+    | ActivityInstance
+    | ReactScopeInstance,
 ): void {
   (node: any)[internalInstanceKey] = hostInst;
 }
@@ -81,15 +88,16 @@ export function isContainerMarkedAsRoot(node: Container): boolean {
 
 // Given a DOM node, return the closest HostComponent or HostText fiber ancestor.
 // If the target node is part of a hydrated or not yet rendered subtree, then
-// this may also return a SuspenseComponent or HostRoot to indicate that.
+// this may also return a SuspenseComponent, ActivityComponent or HostRoot to
+// indicate that.
 // Conceptually the HostRoot fiber is a child of the Container node. So if you
 // pass the Container node as the targetNode, you will not actually get the
 // HostRoot back. To get to the HostRoot, you need to pass a child of it.
-// The same thing applies to Suspense boundaries.
+// The same thing applies to Suspense and Activity boundaries.
 export function getClosestInstanceFromNode(targetNode: Node): null | Fiber {
   let targetInst = (targetNode: any)[internalInstanceKey];
   if (targetInst) {
-    // Don't return HostRoot or SuspenseComponent here.
+    // Don't return HostRoot, SuspenseComponent or ActivityComponent here.
     return targetInst;
   }
   // If the direct event target isn't a React owned DOM node, we need to look
@@ -129,8 +137,8 @@ export function getClosestInstanceFromNode(targetNode: Node): null | Fiber {
       ) {
         // Next we need to figure out if the node that skipped past is
         // nested within a dehydrated boundary and if so, which one.
-        let suspenseInstance = getParentSuspenseInstance(targetNode);
-        while (suspenseInstance !== null) {
+        let hydrationInstance = getParentHydrationBoundary(targetNode);
+        while (hydrationInstance !== null) {
           // We found a suspense instance. That means that we haven't
           // hydrated it yet. Even though we leave the comments in the
           // DOM after hydrating, and there are boundaries in the DOM
@@ -140,15 +148,15 @@ export function getClosestInstanceFromNode(targetNode: Node): null | Fiber {
           // Let's get the fiber associated with the SuspenseComponent
           // as the deepest instance.
           // $FlowFixMe[prop-missing]
-          const targetSuspenseInst = suspenseInstance[internalInstanceKey];
-          if (targetSuspenseInst) {
-            return targetSuspenseInst;
+          const targetFiber = hydrationInstance[internalInstanceKey];
+          if (targetFiber) {
+            return targetFiber;
           }
           // If we don't find a Fiber on the comment, it might be because
           // we haven't gotten to hydrate it yet. There might still be a
           // parent boundary that hasn't above this one so we need to find
           // the outer most that is known.
-          suspenseInstance = getParentSuspenseInstance(suspenseInstance);
+          hydrationInstance = getParentHydrationBoundary(hydrationInstance);
           // If we don't find one, then that should mean that the parent
           // host component also hasn't hydrated yet. We can return it
           // below since it will bail out on the isMounted check later.
@@ -176,6 +184,7 @@ export function getInstanceFromNode(node: Node): Fiber | null {
       tag === HostComponent ||
       tag === HostText ||
       tag === SuspenseComponent ||
+      tag === ActivityComponent ||
       tag === HostHoistable ||
       tag === HostSingleton ||
       tag === HostRoot
@@ -211,15 +220,17 @@ export function getNodeFromInstance(inst: Fiber): Instance | TextInstance {
 }
 
 export function getFiberCurrentPropsFromNode(
-  node: Container | Instance | TextInstance | SuspenseInstance,
+  node:
+    | Container
+    | Instance
+    | TextInstance
+    | SuspenseInstance
+    | ActivityInstance,
 ): Props {
   return (node: any)[internalPropsKey] || null;
 }
 
-export function updateFiberProps(
-  node: Instance | TextInstance | SuspenseInstance,
-  props: Props,
-): void {
+export function updateFiberProps(node: Instance, props: Props): void {
   (node: any)[internalPropsKey] = props;
 }