Revert "Scribble mixin (flutter#104128)" (flutter#114647)

This reverts commit b571abf.

packages/flutter/lib/services.dart

@@ -37,7 +37,6 @@ export 'src/services/raw_keyboard_macos.dart';
 export 'src/services/raw_keyboard_web.dart';
 export 'src/services/raw_keyboard_windows.dart';
 export 'src/services/restoration.dart';
-export 'src/services/scribble.dart';
 export 'src/services/service_extensions.dart';
 export 'src/services/spell_check.dart';
 export 'src/services/system_channels.dart';

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

@@ -15,9 +15,9 @@ import 'binary_messenger.dart';
 import 'hardware_keyboard.dart';
 import 'message_codec.dart';
 import 'restoration.dart';
-import 'scribble.dart';
 import 'service_extensions.dart';
 import 'system_channels.dart';
+import 'text_input.dart';
 
 export 'dart:ui' show ChannelBuffers, RootIsolateToken;
 
@@ -43,7 +43,7 @@ mixin ServicesBinding on BindingBase, SchedulerBinding {
     SystemChannels.system.setMessageHandler((dynamic message) => handleSystemMessage(message as Object));
     SystemChannels.lifecycle.setMessageHandler(_handleLifecycleMessage);
     SystemChannels.platform.setMethodCallHandler(_handlePlatformMessage);
-    Scribble.ensureInitialized();
+    TextInput.ensureInitialized();
     readInitialLifecycleStateFromNativeWindow();
   }
 
@@ -326,6 +326,7 @@ mixin ServicesBinding on BindingBase, SchedulerBinding {
   void setSystemUiChangeCallback(SystemUiChangeCallback? callback) {
     _systemUiChangeCallback = callback;
   }
+
 }
 
 /// Signature for listening to changes in the [SystemUiMode].

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

@@ -222,38 +222,6 @@ class SystemChannels {
       JSONMethodCodec(),
   );
 
-  /// A JSON [MethodChannel] for handling handwriting input.
-  ///
-  /// This method channel is used by iPadOS 14's Scribble feature where writing
-  /// with an Apple Pencil on top of a text field inserts text into the field.
-  ///
-  /// The following methods are defined for this channel:
-  ///
-  ///  * `Scribble.focusElement`: Indicates that focus is requested at the given
-  ///    [Offset].
-  ///
-  ///  * `Scribble.requestElementsInRect`: Returns a List of identifiers and
-  ///    bounds for the [ScribbleClient]s that lie within the given Rect.
-  ///
-  ///  * `Scribble.scribbleInteractionBegan`: Indicates that handwriting input
-  ///    has started.
-  ///
-  ///  * `Scribble.scribbleInteractionFinished`: Indicates that handwriting input
-  ///    has ended.
-  ///
-  ///  * `Scribble.showToolbar`: Requests that the toolbar be shown, such as
-  ///    when selection is changed by handwriting.
-  ///
-  ///  * `Scribble.insertTextPlaceholder`: Requests that visual writing space is
-  ///    reserved.
-  ///
-  ///  * `Scribble.removeTextPlaceholder`: Requests that any placeholder writing
-  ///    space is removed.
-  static const MethodChannel scribble = OptionalMethodChannel(
-      'flutter/scribble',
-      JSONMethodCodec(),
-  );
-
   /// A [MethodChannel] for handling spell check for text input.
   ///
   /// This channel exposes the spell check framework for supported platforms.