Revert "Remove redundant hide handles API from TextSelectionDelegate (#98944)" (#99008)

This reverts commit 94f6fd6e.

packages/flutter/lib/src/services/text_input.dart

@@ -990,6 +990,13 @@ mixin TextSelectionDelegate {
   ///   updating the text editing state.
   void userUpdateTextEditingValue(TextEditingValue value, SelectionChangedCause cause);
 
+  /// Hides the text selection toolbar.
+  ///
+  /// By default, hideHandles is true, and the toolbar is hidden along with its
+  /// handles. If hideHandles is set to false, then the toolbar will be hidden
+  /// but the handles will remain.
+  void hideToolbar([bool hideHandles = true]);
+
   /// Brings the provided [TextPosition] into the visible area of the text
   /// input.
   void bringIntoView(TextPosition position);

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

@@ -2908,11 +2908,7 @@ class EditableTextState extends State<EditableText> with AutomaticKeepAliveClien
     return true;
   }
 
-  /// Hides the text selection toolbar.
-  ///
-  /// By default, hideHandles is true, and the toolbar is hidden along with its
-  /// handles. If hideHandles is set to false, then the toolbar will be hidden
-  /// but the handles will remain.
+  @override
   void hideToolbar([bool hideHandles = true]) {
     if (hideHandles) {
       // Hide the handles and the toolbar.

packages/flutter/test/rendering/editable_test.dart

@@ -27,6 +27,9 @@ class _FakeEditableTextState with TextSelectionDelegate {
   @override
   TextEditingValue textEditingValue = TextEditingValue.empty;
 
+  @override
+  void hideToolbar([bool hideHandles = true]) { }
+
   @override
   void userUpdateTextEditingValue(TextEditingValue value, SelectionChangedCause cause) { }