Scaffold drawer fix (#23689)

* Adds drawer state query functions

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

@@ -1045,6 +1045,22 @@ class ScaffoldState extends State<Scaffold> with TickerProviderStateMixin {
   bool _drawerOpened = false;
   bool _endDrawerOpened = false;
 
+  /// Whether the [Scaffold.drawer] is opened.
+  ///
+  /// See also:
+  ///
+  ///   * [ScaffoldState.openDrawer], which opens the [Scaffold.drawer] of a
+  ///   [Scaffold].
+  bool get isDrawerOpen => _drawerOpened;
+
+  /// Whether the [Scaffold.endDrawer] is opened.
+  ///
+  /// See also:
+  ///
+  ///   * [ScaffoldState.openEndDrawer], which opens the [Scaffold.endDrawer] of
+  ///     a [Scaffold].
+  bool get isEndDrawerOpen => _endDrawerOpened;
+
   void _drawerOpenedCallback(bool isOpened) {
     setState(() {
       _drawerOpened = isOpened;

packages/flutter/test/material/scaffold_test.dart

@@ -998,8 +998,60 @@ void main() {
       semantics.dispose();
     });
 
-    testWidgets('Dual Drawer Opening', (WidgetTester tester) async {
+    testWidgets('Drawer state query correctly', (WidgetTester tester) async {
+      await tester.pumpWidget(
+        MaterialApp(
+          home: SafeArea(
+            left: false,
+            top: true,
+            right: false,
+            bottom: false,
+            child: Scaffold(
+              endDrawer: const Drawer(
+                child: Text('endDrawer'),
+              ),
+              drawer: const Drawer(
+                child: Text('drawer'),
+              ),
+              body: const Text('scaffold body'),
+              appBar: AppBar(
+                centerTitle: true,
+                title: const Text('Title')
+              ),
+            ),
+          ),
+        ),
+      );
 
+      final ScaffoldState scaffoldState = tester.state(find.byType(Scaffold));
+
+      final Finder drawerOpenButton = find.byType(IconButton).first;
+      final Finder endDrawerOpenButton = find.byType(IconButton).last;
+
+      await tester.tap(drawerOpenButton);
+      await tester.pumpAndSettle();
+      expect(true, scaffoldState.isDrawerOpen);
+      await tester.tap(endDrawerOpenButton);
+      await tester.pumpAndSettle();
+      expect(false, scaffoldState.isDrawerOpen);
+
+      await tester.tap(endDrawerOpenButton);
+      await tester.pumpAndSettle();
+      expect(true, scaffoldState.isEndDrawerOpen);
+      await tester.tap(drawerOpenButton);
+      await tester.pumpAndSettle();
+      expect(false, scaffoldState.isEndDrawerOpen);
+
+      scaffoldState.openDrawer();
+      expect(true, scaffoldState.isDrawerOpen);
+      await tester.tap(drawerOpenButton);
+      await tester.pumpAndSettle();
+
+      scaffoldState.openEndDrawer();
+      expect(true, scaffoldState.isEndDrawerOpen);
+    });
+
+    testWidgets('Dual Drawer Opening', (WidgetTester tester) async {
       await tester.pumpWidget(
         MaterialApp(
           home: SafeArea(