Fix: Initialize childIndex in Task constructor (#27367)

This field was not being initialized. Although the property is part of
the Flow type, the type error wasn't caught because the constructor
itself is not covered by Flow, which is unfortunate. (I assume this is
related to the dev-only componentStack property.)

DiffTrain build for commit https://github.com/facebook/react/commit/69be472c11231056d297a7b73dd0b121905606d3.

compiled-rn/facebook-fbsource/xplat/js/RKJSModules/vendor/react-test-renderer/cjs/ReactTestRenderer-dev.js

@@ -23994,7 +23994,7 @@ function createFiberRoot(
   return root;
 }
 
-var ReactVersion = "18.3.0-canary-d07921eed-20230912";
+var ReactVersion = "18.3.0-canary-69be472c1-20230912";
 
 // Might add PROFILE later.
 

compiled-rn/facebook-fbsource/xplat/js/RKJSModules/vendor/react-test-renderer/cjs/ReactTestRenderer-prod.js

@@ -8617,7 +8617,7 @@ var devToolsConfig$jscomp$inline_1027 = {
     throw Error("TestRenderer does not support findFiberByHostInstance()");
   },
   bundleType: 0,
-  version: "18.3.0-canary-d07921eed-20230912",
+  version: "18.3.0-canary-69be472c1-20230912",
   rendererPackageName: "react-test-renderer"
 };
 var internals$jscomp$inline_1226 = {
@@ -8648,7 +8648,7 @@ var internals$jscomp$inline_1226 = {
   scheduleRoot: null,
   setRefreshHandler: null,
   getCurrentFiber: null,
-  reconcilerVersion: "18.3.0-canary-d07921eed-20230912"
+  reconcilerVersion: "18.3.0-canary-69be472c1-20230912"
 };
 if ("undefined" !== typeof __REACT_DEVTOOLS_GLOBAL_HOOK__) {
   var hook$jscomp$inline_1227 = __REACT_DEVTOOLS_GLOBAL_HOOK__;

compiled-rn/facebook-fbsource/xplat/js/RKJSModules/vendor/react-test-renderer/cjs/ReactTestRenderer-profiling.js

@@ -9043,7 +9043,7 @@ var devToolsConfig$jscomp$inline_1069 = {
     throw Error("TestRenderer does not support findFiberByHostInstance()");
   },
   bundleType: 0,
-  version: "18.3.0-canary-d07921eed-20230912",
+  version: "18.3.0-canary-69be472c1-20230912",
   rendererPackageName: "react-test-renderer"
 };
 var internals$jscomp$inline_1267 = {
@@ -9074,7 +9074,7 @@ var internals$jscomp$inline_1267 = {
   scheduleRoot: null,
   setRefreshHandler: null,
   getCurrentFiber: null,
-  reconcilerVersion: "18.3.0-canary-d07921eed-20230912"
+  reconcilerVersion: "18.3.0-canary-69be472c1-20230912"
 };
 if ("undefined" !== typeof __REACT_DEVTOOLS_GLOBAL_HOOK__) {
   var hook$jscomp$inline_1268 = __REACT_DEVTOOLS_GLOBAL_HOOK__;

compiled-rn/facebook-fbsource/xplat/js/RKJSModules/vendor/react/cjs/React-dev.js

@@ -27,7 +27,7 @@ if (
 }
           "use strict";
 
-var ReactVersion = "18.3.0-canary-d07921eed-20230912";
+var ReactVersion = "18.3.0-canary-69be472c1-20230912";
 
 // ATTENTION
 // When adding new symbols to this file,

compiled-rn/facebook-fbsource/xplat/js/RKJSModules/vendor/react/cjs/React-prod.js

@@ -616,4 +616,4 @@ exports.useSyncExternalStore = function (
 exports.useTransition = function () {
   return ReactCurrentDispatcher.current.useTransition();
 };
-exports.version = "18.3.0-canary-d07921eed-20230912";
+exports.version = "18.3.0-canary-69be472c1-20230912";

compiled-rn/facebook-fbsource/xplat/js/RKJSModules/vendor/react/cjs/React-profiling.js

@@ -619,7 +619,7 @@ exports.useSyncExternalStore = function (
 exports.useTransition = function () {
   return ReactCurrentDispatcher.current.useTransition();
 };
-exports.version = "18.3.0-canary-d07921eed-20230912";
+exports.version = "18.3.0-canary-69be472c1-20230912";
 
           /* global __REACT_DEVTOOLS_GLOBAL_HOOK__ */
 if (

compiled-rn/facebook-fbsource/xplat/js/react-native-github/Libraries/Renderer/REVISION

@@ -1 +1 @@
-d07921eeda62613bfcf52ecdb66322db26393567
+69be472c11231056d297a7b73dd0b121905606d3