Fix: Synchronous popstate transitions (#30759)

This is a refactor of the fix in #27505.

When a transition update is scheduled by a popstate event, (i.e. a back/
forward navigation) we attempt to render it synchronously even though
it's a transition, since it's likely the previous page's data is cached.

In #27505, I changed the implementation so that it only "upgrades" the
priority of the transition for a single attempt. If the attempt
suspends, say because the data is not cached after all, from then on it
should be treated as a normal transition.

But it turns out #27505 did not work as intended, because it relied on
marking the root with pending synchronous work (root.pendingLanes),
which was never cleared until the popstate update completed.

The test scenarios I wrote accidentally worked for a different reason
related to suspending the work loop, which I'm currently in the middle
of refactoring.

DiffTrain build for commit ee7f675.

compiled-rn/VERSION_NATIVE_FB

@@ -1 +1 @@
-19.0.0-native-fb-85fb95cd-20240816
+19.0.0-native-fb-ee7f6757-20240823

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

@@ -7,13 +7,13 @@
  * @noflow
  * @nolint
  * @preventMunge
- * @generated SignedSource<<7279cc9cb0c567689cd8628192884a45>>
+ * @generated SignedSource<<487e4d25726d3b9452e5df47a0ff70f5>>
  */
 
 "use strict";
 __DEV__ &&
   (function () {
-    function JSCompiler_object_inline_createNodeMock_1088() {
+    function JSCompiler_object_inline_createNodeMock_1089() {
       return null;
     }
     function findHook(fiber, id) {
@@ -1789,28 +1789,41 @@ __DEV__ &&
         0 === root.tag &&
         (ReactSharedInternals.didScheduleLegacyUpdate = !0);
     }
-    function flushSyncWorkAcrossRoots_impl(onlyLegacy) {
+    function flushSyncWorkAcrossRoots_impl(syncTransitionLanes, onlyLegacy) {
       if (!isFlushingWork && mightHavePendingSyncWork) {
         isFlushingWork = !0;
         do {
           var didPerformSomeWork = !1;
           for (var root = firstScheduledRoot; null !== root; ) {
-            if (!onlyLegacy || 0 === root.tag) {
-              var workInProgressRootRenderLanes$jscomp$0 =
-                workInProgressRootRenderLanes;
-              workInProgressRootRenderLanes$jscomp$0 = getNextLanes(
-                root,
-                root === workInProgressRoot
-                  ? workInProgressRootRenderLanes$jscomp$0
-                  : 0
-              );
-              0 !== (workInProgressRootRenderLanes$jscomp$0 & 3) &&
-                ((didPerformSomeWork = !0),
-                performSyncWorkOnRoot(
-                  root,
-                  workInProgressRootRenderLanes$jscomp$0
-                ));
-            }
+            if (!onlyLegacy || 0 === root.tag)
+              if (0 !== syncTransitionLanes) {
+                var pendingLanes = root.pendingLanes;
+                if (0 === pendingLanes) var nextLanes = 0;
+                else {
+                  var suspendedLanes = root.suspendedLanes,
+                    pingedLanes = root.pingedLanes;
+                  nextLanes =
+                    (1 << (31 - clz32(42 | syncTransitionLanes) + 1)) - 1;
+                  nextLanes &= pendingLanes & ~(suspendedLanes & ~pingedLanes);
+                  nextLanes =
+                    nextLanes & 201326677
+                      ? (nextLanes & 201326677) | 1
+                      : nextLanes
+                        ? nextLanes | 2
+                        : 0;
+                }
+                0 !== nextLanes &&
+                  ((didPerformSomeWork = !0),
+                  performSyncWorkOnRoot(root, nextLanes));
+              } else
+                (nextLanes = workInProgressRootRenderLanes),
+                  (nextLanes = getNextLanes(
+                    root,
+                    root === workInProgressRoot ? nextLanes : 0
+                  )),
+                  0 !== (nextLanes & 3) &&
+                    ((didPerformSomeWork = !0),
+                    performSyncWorkOnRoot(root, nextLanes));
             root = root.next;
           }
         } while (didPerformSomeWork);
@@ -1822,6 +1835,7 @@ __DEV__ &&
         didScheduleMicrotask_act =
         didScheduleMicrotask =
           !1;
+      0 !== currentEventTransitionLane && (currentEventTransitionLane = 0);
       for (
         var currentTime = now$1(), prev = null, root = firstScheduledRoot;
         null !== root;
@@ -1837,8 +1851,7 @@ __DEV__ &&
             0 !== (nextLanes & 3) && (mightHavePendingSyncWork = !0));
         root = next;
       }
-      currentEventTransitionLane = 0;
-      flushSyncWorkAcrossRoots_impl(!1);
+      flushSyncWorkAcrossRoots_impl(0, !1);
     }
     function scheduleTaskForRootDuringMicrotask(root, currentTime) {
       for (
@@ -10536,7 +10549,7 @@ __DEV__ &&
             0 !== (fiber.mode & 1) ||
             ReactSharedInternals.isBatchingLegacy ||
             ((workInProgressRootRenderTargetTime = now$1() + RENDER_TIMEOUT_MS),
-            flushSyncWorkAcrossRoots_impl(!0));
+            flushSyncWorkAcrossRoots_impl(0, !0));
     }
     function performConcurrentWorkOnRoot(root, didTimeout) {
       nestedUpdateScheduled = currentUpdateIsNested = !1;
@@ -10861,12 +10874,12 @@ __DEV__ &&
           (ReactSharedInternals.T = prevTransition),
           (executionContext = prevExecutionContext),
           (executionContext & (RenderContext | CommitContext)) === NoContext &&
-            flushSyncWorkAcrossRoots_impl(!1);
+            flushSyncWorkAcrossRoots_impl(0, !1);
       }
     }
     function flushSyncWork() {
       return (executionContext & (RenderContext | CommitContext)) === NoContext
-        ? (flushSyncWorkAcrossRoots_impl(!1), !1)
+        ? (flushSyncWorkAcrossRoots_impl(0, !1), !1)
         : !0;
     }
     function resetWorkInProgressStack() {
@@ -11549,7 +11562,7 @@ __DEV__ &&
             ? nestedUpdateCount++
             : ((nestedUpdateCount = 0), (rootWithNestedUpdates = root)))
         : (nestedUpdateCount = 0);
-      flushSyncWorkAcrossRoots_impl(!1);
+      flushSyncWorkAcrossRoots_impl(0, !1);
       markCommitStopped();
       return null;
     }
@@ -11679,7 +11692,7 @@ __DEV__ &&
               injectedProfilingHooks.markPassiveEffectsStopped();
             commitDoubleInvokeEffectsInDEV(priority, !0);
             executionContext = prevExecutionContext;
-            flushSyncWorkAcrossRoots_impl(!1);
+            flushSyncWorkAcrossRoots_impl(0, !1);
             didScheduleUpdateDuringPassiveEffects
               ? priority === rootWithPassiveNestedUpdates
                 ? nestedPassiveUpdateCount++
@@ -14925,11 +14938,11 @@ __DEV__ &&
     (function () {
       var internals = {
         bundleType: 1,
-        version: "19.0.0-native-fb-85fb95cd-20240816",
+        version: "19.0.0-native-fb-ee7f6757-20240823",
         rendererPackageName: "react-test-renderer",
         currentDispatcherRef: ReactSharedInternals,
         findFiberByHostInstance: getInstanceFromNode,
-        reconcilerVersion: "19.0.0-native-fb-85fb95cd-20240816"
+        reconcilerVersion: "19.0.0-native-fb-ee7f6757-20240823"
       };
       internals.overrideHookState = overrideHookState;
       internals.overrideHookStateDeletePath = overrideHookStateDeletePath;
@@ -14951,7 +14964,7 @@ __DEV__ &&
     exports._Scheduler = Scheduler;
     exports.act = act;
     exports.create = function (element, options) {
-      var createNodeMock = JSCompiler_object_inline_createNodeMock_1088,
+      var createNodeMock = JSCompiler_object_inline_createNodeMock_1089,
         isConcurrent = !1,
         isStrictMode = !1;
       "object" === typeof options &&
@@ -15071,8 +15084,8 @@ __DEV__ &&
           executionContext !== NoContext ||
             ReactSharedInternals.isBatchingLegacy ||
             ((workInProgressRootRenderTargetTime = now$1() + RENDER_TIMEOUT_MS),
-            flushSyncWorkAcrossRoots_impl(!0));
+            flushSyncWorkAcrossRoots_impl(0, !0));
       }
     };
-    exports.version = "19.0.0-native-fb-85fb95cd-20240816";
+    exports.version = "19.0.0-native-fb-ee7f6757-20240823";
   })();