Fix error message and other typos (#25126)

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

@@ -99,8 +99,8 @@ class CupertinoTabBar extends StatelessWidget implements PreferredSizeWidget {
 
   /// The size of all of the [BottomNavigationBarItem] icons.
   ///
-  /// This value is used to to configure the [IconTheme] for the navigation
-  /// bar. When a [BottomNavigationBarItem.icon] widget is not an [Icon] the widget
+  /// This value is used to configure the [IconTheme] for the navigation bar.
+  /// When a [BottomNavigationBarItem.icon] widget is not an [Icon] the widget
   /// should configure itself to match the icon theme's size and color.
   ///
   /// Must not be null.

packages/flutter/lib/src/semantics/semantics.dart

@@ -2445,7 +2445,7 @@ class SemanticsOwner extends ChangeNotifier {
 /// Describes the semantic information associated with the owning
 /// [RenderObject].
 ///
-/// The information provided in the configuration is used to to generate the
+/// The information provided in the configuration is used to generate the
 /// semantics tree.
 class SemanticsConfiguration {
 

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

@@ -3924,7 +3924,7 @@ class StatefulElement extends ComponentElement {
           'the inherited widget is in a constructor or an initState() method, '
           'then the rebuilt dependent widget will not reflect the changes in the '
           'inherited widget.\n'
-          'Typically references to to inherited widgets should occur in widget build() methods. Alternatively, '
+          'Typically references to inherited widgets should occur in widget build() methods. Alternatively, '
           'initialization based on inherited widgets can be placed in the didChangeDependencies method, which '
           'is called after initState and whenever the dependencies change thereafter.'
         );