Handle SuspenseListComponent getting retried (#16745)

This happens for example when a deleted boundary transfers its pending
promises to the list so that the list can be retried.

This wasn't caught by unit tests because this flag wasn't on in those
tests.

Author: sebmarkbage

packages/react-reconciler/src/ReactFiberWorkLoop.js

@@ -77,6 +77,7 @@ import {
   HostRoot,
   ClassComponent,
   SuspenseComponent,
+  SuspenseListComponent,
   FunctionComponent,
   ForwardRef,
   MemoComponent,
@@ -2223,6 +2224,9 @@ export function resolveRetryThenable(boundaryFiber: Fiber, thenable: Thenable) {
           retryTime = suspenseState.retryTime;
         }
         break;
+      case SuspenseListComponent:
+        retryCache = boundaryFiber.stateNode;
+        break;
       default:
         invariant(
           false,

packages/react-reconciler/src/__tests__/ReactSuspenseList-test.internal.js

@@ -11,6 +11,7 @@ describe('ReactSuspenseList', () => {
     ReactFeatureFlags = require('shared/ReactFeatureFlags');
     ReactFeatureFlags.debugRenderPhaseSideEffectsForStrictMode = false;
     ReactFeatureFlags.replayFailedUnitOfWorkWithInvokeGuardedCallback = false;
+    ReactFeatureFlags.enableSuspenseServerRenderer = true;
     React = require('react');
     ReactNoop = require('react-noop-renderer');
     Scheduler = require('scheduler');