remove some stray nullOK mentions from docs (#74661)

packages/flutter/lib/src/cupertino/interface_level.dart

@@ -24,12 +24,14 @@ enum CupertinoUserInterfaceLevelData {
 /// the given data.
 ///
 /// Querying the current elevation status using [CupertinoUserInterfaceLevel.of]
-/// will cause your widget to rebuild automatically whenever the [CupertinoUserInterfaceLevelData]
-/// changes.
+/// will cause your widget to rebuild automatically whenever the
+/// [CupertinoUserInterfaceLevelData] changes.
 ///
-/// If no [CupertinoUserInterfaceLevel] is in scope then the [CupertinoUserInterfaceLevel.of]
-/// method will throw an exception, unless the `nullOk` argument is set to true,
-/// in which case it returns null.
+/// If no [CupertinoUserInterfaceLevel] is in scope then the
+/// [CupertinoUserInterfaceLevel.of] method will throw an exception.
+/// Alternatively, [CupertinoUserInterfaceLevel.maybeOf] can be used, which
+/// returns null instead of throwing if no [CupertinoUserInterfaceLevel] is in
+/// scope.
 ///
 /// See also:
 ///

packages/flutter/lib/src/material/about.dart

@@ -1199,18 +1199,16 @@ class _MasterDetailFlow extends StatefulWidget {
   /// ```dart
   /// _MasterDetailFlow.of(context).openDetailPage(arguments);
   /// ```
-  static _MasterDetailFlowProxy? of(
-      BuildContext context, {
-        bool nullOk = false,
-      }) {
+  static _MasterDetailFlowProxy? of(BuildContext context) {
     _PageOpener? pageOpener = context.findAncestorStateOfType<_MasterDetailScaffoldState>();
     pageOpener ??= context.findAncestorStateOfType<_MasterDetailFlowState>();
     assert(() {
-      if (pageOpener == null && !nullOk) {
+      if (pageOpener == null) {
         throw FlutterError(
-            'Master Detail operation requested with a context that does not include a Master Detail'
-                ' Flow.\nThe context used to open a detail page from the Master Detail Flow must be'
-                ' that of a widget that is a descendant of a Master Detail Flow widget.');
+          'Master Detail operation requested with a context that does not include a Master Detail '
+          'Flow.\nThe context used to open a detail page from the Master Detail Flow must be '
+          'that of a widget that is a descendant of a Master Detail Flow widget.'
+        );
       }
       return true;
     }());

packages/flutter/lib/src/material/scaffold.dart

@@ -2796,8 +2796,8 @@ class ScaffoldState extends State<Scaffold> with TickerProviderStateMixin, Resto
 
   @override
   void didChangeDependencies() {
-    // nullOk is valid here since  both the Scaffold and ScaffoldMessenger are
-    // currently available for managing SnackBars.
+    // Using maybeOf is valid here since both the Scaffold and ScaffoldMessenger
+    // are currently available for managing SnackBars.
     final ScaffoldMessengerState? _currentScaffoldMessenger = ScaffoldMessenger.maybeOf(context);
     // If our ScaffoldMessenger has changed, unregister with the old one first.
     if (_scaffoldMessenger != null &&

packages/flutter/lib/src/widgets/media_query.dart

@@ -31,8 +31,8 @@ enum Orientation {
 /// window, use `MediaQuery.of(context).size`.
 ///
 /// If no [MediaQuery] is in scope then the [MediaQuery.of] method will throw an
-/// exception, unless the `nullOk` argument is set to true, in which case it
-/// returns null.
+/// exception. Alternatively, [MediaQuery.maybeOf] may be used, which returns
+/// null instead of throwing if no [MediaQuery] is in scope.
 ///
 /// ## Insets and Padding
 ///
@@ -629,8 +629,8 @@ class MediaQueryData {
 /// user rotates their device).
 ///
 /// If no [MediaQuery] is in scope then the [MediaQuery.of] method will throw an
-/// exception, unless the `nullOk` argument is set to true, in which case it
-/// returns null.
+/// exception. Alternatively, [MediaQuery.maybeOf] may be used, which returns
+/// null instead of throwing if no [MediaQuery] is in scope.
 ///
 /// {@youtube 560 315 https://www.youtube.com/watch?v=A3WrA4zAaPw}
 ///

packages/flutter/test/widgets/router_test.dart

@@ -88,7 +88,6 @@ void main() {
     Router<dynamic>? router = Router.maybeOf(textContext);
     expect(router, isNull);
 
-    // Test when the nullOk is not specified.
     bool hasFlutterError = false;
     try {
       router = Router.of(textContext);