[Fizz] Don't bail out of flushing if we still have pending root tasks (#27385)

The idea for this check is that we shouldn't flush anything before we
flush the shell. That may or may not hold true in future formats like
RN.

It is a problem for resuming because with resuming it's possible to have
root tasks that are used for resuming but the shell was already flushed
so we can have completed boundaries before the shell has fully resumed.
What matters is whether the parent has already flushed or not.

It's not technically necessary to bail early because there won't be
anything in partialBoundaries or completedBoundaries because nothing
gets added there unless the parent has already flushed.

It's not exactly slow to have to check the length of three arrays so
it's probably not a big deal.

Flush partials in an early preamble needs further consideration
regardless.

DiffTrain build for commit df061b3.

Author: sebmarkbage

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

@@ -23998,7 +23998,7 @@ function createFiberRoot(
   return root;
 }
 
-var ReactVersion = "18.3.0-canary-a5fc797db-20230915";
+var ReactVersion = "18.3.0-canary-df061b396-20230918";
 
 // Might add PROFILE later.
 

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

@@ -8620,7 +8620,7 @@ var devToolsConfig$jscomp$inline_1028 = {
     throw Error("TestRenderer does not support findFiberByHostInstance()");
   },
   bundleType: 0,
-  version: "18.3.0-canary-a5fc797db-20230915",
+  version: "18.3.0-canary-df061b396-20230918",
   rendererPackageName: "react-test-renderer"
 };
 var internals$jscomp$inline_1227 = {
@@ -8651,7 +8651,7 @@ var internals$jscomp$inline_1227 = {
   scheduleRoot: null,
   setRefreshHandler: null,
   getCurrentFiber: null,
-  reconcilerVersion: "18.3.0-canary-a5fc797db-20230915"
+  reconcilerVersion: "18.3.0-canary-df061b396-20230918"
 };
 if ("undefined" !== typeof __REACT_DEVTOOLS_GLOBAL_HOOK__) {
   var hook$jscomp$inline_1228 = __REACT_DEVTOOLS_GLOBAL_HOOK__;

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

@@ -9046,7 +9046,7 @@ var devToolsConfig$jscomp$inline_1070 = {
     throw Error("TestRenderer does not support findFiberByHostInstance()");
   },
   bundleType: 0,
-  version: "18.3.0-canary-a5fc797db-20230915",
+  version: "18.3.0-canary-df061b396-20230918",
   rendererPackageName: "react-test-renderer"
 };
 var internals$jscomp$inline_1268 = {
@@ -9077,7 +9077,7 @@ var internals$jscomp$inline_1268 = {
   scheduleRoot: null,
   setRefreshHandler: null,
   getCurrentFiber: null,
-  reconcilerVersion: "18.3.0-canary-a5fc797db-20230915"
+  reconcilerVersion: "18.3.0-canary-df061b396-20230918"
 };
 if ("undefined" !== typeof __REACT_DEVTOOLS_GLOBAL_HOOK__) {
   var hook$jscomp$inline_1269 = __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-a5fc797db-20230915";
+var ReactVersion = "18.3.0-canary-df061b396-20230918";
 
 // 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-a5fc797db-20230915";
+exports.version = "18.3.0-canary-df061b396-20230918";

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-a5fc797db-20230915";
+exports.version = "18.3.0-canary-df061b396-20230918";
 
           /* global __REACT_DEVTOOLS_GLOBAL_HOOK__ */
 if (

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

@@ -1 +1 @@
-a5fc797db14c6e05d4d5c4dbb22a0dd70d41f5d5
+df061b396644bb7c27ea76bb27ae09784ce6444b