Cleanup enableUseRefAccessWarning flag (#28699)

Cleanup enableUseRefAccessWarning flag

I don't think this flag has a path forward in the current
implementation. The detection by stack trace is too brittle to detect
the lazy initialization pattern reliably (see e.g. some internal tests
that expect the warning because they use lazy intialization, but a
slightly different pattern then the expected pattern.

I think a new version of this could be to fully ban ref access during
render with an alternative API for the exceptional cases that today
require ref access during render.

DiffTrain build for commit 20e710a.

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

@@ -7,7 +7,7 @@
  * @noflow
  * @nolint
  * @preventMunge
- * @generated SignedSource<<9049da9d0398addbe9ad47567cb0a0f2>>
+ * @generated SignedSource<<dff5882f8219f97fa6b685d700750e06>>
  */
 
 "use strict";
@@ -9818,14 +9818,11 @@ if (__DEV__) {
 
     function mountRef(initialValue) {
       var hook = mountWorkInProgressHook();
-
-      {
-        var _ref2 = {
-          current: initialValue
-        };
-        hook.memoizedState = _ref2;
-        return _ref2;
-      }
+      var ref = {
+        current: initialValue
+      };
+      hook.memoizedState = ref;
+      return ref;
     }
 
     function updateRef(initialValue) {
@@ -26801,7 +26798,7 @@ if (__DEV__) {
       return root;
     }
 
-    var ReactVersion = "19.0.0-canary-23a1aa6f";
+    var ReactVersion = "19.0.0-canary-9dd5e9f4";
 
     // Might add PROFILE later.
 

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

@@ -1 +1 @@
-7a2609eedc571049a3272e60d5f7d84601ffca3f
+20e710aeab3e03809c82d134171986ea270026a0

compiled-rn/facebook-fbsource/xplat/js/react-native-github/Libraries/Renderer/implementations/ReactFabric-dev.fb.js

@@ -7,7 +7,7 @@
  * @noflow
  * @nolint
  * @preventMunge
- * @generated SignedSource<<83ce9566209d54efec3736b91598c233>>
+ * @generated SignedSource<<cb885e8934a011f045924ca7dbd54aba>>
  */
 
 "use strict";
@@ -2984,7 +2984,6 @@ to return true:wantsResponderID|                            |
         dynamicFlags.enableInfiniteRenderLoopDetection,
       enableRenderableContext = dynamicFlags.enableRenderableContext,
       enableUnifiedSyncLane = dynamicFlags.enableUnifiedSyncLane,
-      enableUseRefAccessWarning = dynamicFlags.enableUseRefAccessWarning,
       passChildrenWhenCloningPersistedNodes =
         dynamicFlags.passChildrenWhenCloningPersistedNodes,
       useModernStrictMode = dynamicFlags.useModernStrictMode; // The rest of the flags are static for better dead code elimination.
@@ -13309,95 +13308,13 @@ to return true:wantsResponderID|                            |
       };
     }
 
-    var stackContainsErrorMessage = null;
-
-    function getCallerStackFrame() {
-      // eslint-disable-next-line react-internal/prod-error-codes
-      var stackFrames = new Error("Error message").stack.split("\n"); // Some browsers (e.g. Chrome) include the error message in the stack
-      // but others (e.g. Firefox) do not.
-
-      if (stackContainsErrorMessage === null) {
-        stackContainsErrorMessage = stackFrames[0].includes("Error message");
-      }
-
-      return stackContainsErrorMessage
-        ? stackFrames.slice(3, 4).join("\n")
-        : stackFrames.slice(2, 3).join("\n");
-    }
-
     function mountRef(initialValue) {
       var hook = mountWorkInProgressHook();
-
-      if (enableUseRefAccessWarning) {
-        {
-          // Support lazy initialization pattern shown in docs.
-          // We need to store the caller stack frame so that we don't warn on subsequent renders.
-          var hasBeenInitialized = initialValue != null;
-          var lazyInitGetterStack = null;
-          var didCheckForLazyInit = false; // Only warn once per component+hook.
-
-          var didWarnAboutRead = false;
-          var didWarnAboutWrite = false;
-          var current = initialValue;
-          var ref = {
-            get current() {
-              if (!hasBeenInitialized) {
-                didCheckForLazyInit = true;
-                lazyInitGetterStack = getCallerStackFrame();
-              } else if (
-                currentlyRenderingFiber$1 !== null &&
-                !didWarnAboutRead
-              ) {
-                if (
-                  lazyInitGetterStack === null ||
-                  lazyInitGetterStack !== getCallerStackFrame()
-                ) {
-                  didWarnAboutRead = true;
-
-                  warn(
-                    "%s: Unsafe read of a mutable value during render.\n\n" +
-                      "Reading from a ref during render is only safe if:\n" +
-                      "1. The ref value has not been updated, or\n" +
-                      "2. The ref holds a lazily-initialized value that is only set once.\n",
-                    getComponentNameFromFiber(currentlyRenderingFiber$1) ||
-                      "Unknown"
-                  );
-                }
-              }
-
-              return current;
-            },
-
-            set current(value) {
-              if (currentlyRenderingFiber$1 !== null && !didWarnAboutWrite) {
-                if (hasBeenInitialized || !didCheckForLazyInit) {
-                  didWarnAboutWrite = true;
-
-                  warn(
-                    "%s: Unsafe write of a mutable value during render.\n\n" +
-                      "Writing to a ref during render is only safe if the ref holds " +
-                      "a lazily-initialized value that is only set once.\n",
-                    getComponentNameFromFiber(currentlyRenderingFiber$1) ||
-                      "Unknown"
-                  );
-                }
-              }
-
-              hasBeenInitialized = true;
-              current = value;
-            }
-          };
-          Object.seal(ref);
-          hook.memoizedState = ref;
-          return ref;
-        }
-      } else {
-        var _ref2 = {
-          current: initialValue
-        };
-        hook.memoizedState = _ref2;
-        return _ref2;
-      }
+      var ref = {
+        current: initialValue
+      };
+      hook.memoizedState = ref;
+      return ref;
     }
 
     function updateRef(initialValue) {
@@ -30572,7 +30489,7 @@ to return true:wantsResponderID|                            |
       return root;
     }
 
-    var ReactVersion = "19.0.0-canary-d5e5d620";
+    var ReactVersion = "19.0.0-canary-dbb66dd5";
 
     function createPortal$1(
       children,