Feature/twitter keyboard (#161025)

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Fixes https://github.com/flutter/flutter/issues/64801

Example :

```dart
import 'package:flutter/material.dart';

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Centered TextField Example',
      theme: ThemeData(primarySwatch: Colors.blue),
      home: CenteredTextFieldScreen(),
    );
  }
}

class CenteredTextFieldScreen extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text('Centered TextField')),
      body: Center(
        child: Padding(
          padding: const EdgeInsets.all(16.0),
          child: TextField(
            keyboardType: TextInputType.twitter,
            decoration: InputDecoration(
              border: OutlineInputBorder(),
              hintText: 'Enter some text here',
            ),
          ),
        ),
      ),
    );
  }
}
```


https://github.com/user-attachments/assets/5a2a2a4a-6994-44b1-bb0e-395c24012ef8


https://github.com/user-attachments/assets/aefc7bc5-a997-4e0f-a74e-a39a4517c898

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---------

Co-authored-by: Jenn Magder <magder@google.com>

engine/src/flutter/shell/platform/android/io/flutter/embedding/engine/systemchannels/TextInputChannel.java

@@ -718,7 +718,8 @@ public class TextInputChannel {
     URL("TextInputType.url"),
     VISIBLE_PASSWORD("TextInputType.visiblePassword"),
     NONE("TextInputType.none"),
-    WEB_SEARCH("TextInputType.webSearch");
+    WEB_SEARCH("TextInputType.webSearch"),
+    TWITTER("TextInputType.twitter");
 
     static TextInputType fromValue(@NonNull String encodedName) throws NoSuchFieldException {
       for (TextInputType textInputType : TextInputType.values()) {

engine/src/flutter/shell/platform/android/io/flutter/plugin/editing/TextInputPlugin.java

@@ -250,7 +250,8 @@ public class TextInputPlugin implements ListenableEditingState.EditingStateWatch
     int textType = InputType.TYPE_CLASS_TEXT;
     if (type.type == TextInputChannel.TextInputType.MULTILINE) {
       textType |= InputType.TYPE_TEXT_FLAG_MULTI_LINE;
-    } else if (type.type == TextInputChannel.TextInputType.EMAIL_ADDRESS) {
+    } else if (type.type == TextInputChannel.TextInputType.EMAIL_ADDRESS
+        || type.type == TextInputChannel.TextInputType.TWITTER) {
       textType |= InputType.TYPE_TEXT_VARIATION_EMAIL_ADDRESS;
     } else if (type.type == TextInputChannel.TextInputType.URL
         || type.type == TextInputChannel.TextInputType.WEB_SEARCH) {

engine/src/flutter/shell/platform/android/test/io/flutter/plugin/editing/TextInputPluginTest.java

@@ -1390,6 +1390,41 @@ public class TextInputPluginTest {
         editorInfo.inputType, InputType.TYPE_CLASS_TEXT | InputType.TYPE_TEXT_VARIATION_URI);
   }
 
+  @Test
+  public void showTextInput_textInputTypeTwitter() {
+    TestImm testImm = Shadow.extract(ctx.getSystemService(Context.INPUT_METHOD_SERVICE));
+    View testView = new View(ctx);
+    DartExecutor dartExecutor = mock(DartExecutor.class);
+    TextInputChannel textInputChannel = new TextInputChannel(dartExecutor);
+    ScribeChannel scribeChannel = new ScribeChannel(mock(DartExecutor.class));
+    TextInputPlugin textInputPlugin =
+        new TextInputPlugin(
+            testView, textInputChannel, scribeChannel, mock(PlatformViewsController.class));
+    textInputPlugin.setTextInputClient(
+        0,
+        new TextInputChannel.Configuration(
+            false,
+            false,
+            true,
+            true,
+            false,
+            TextInputChannel.TextCapitalization.NONE,
+            new TextInputChannel.InputType(TextInputChannel.TextInputType.TWITTER, false, false),
+            null,
+            null,
+            null,
+            null,
+            null));
+
+    EditorInfo editorInfo = new EditorInfo();
+    InputConnection connection =
+        textInputPlugin.createInputConnection(testView, mock(KeyboardManager.class), editorInfo);
+
+    assertEquals(
+        editorInfo.inputType,
+        InputType.TYPE_CLASS_TEXT | InputType.TYPE_TEXT_VARIATION_EMAIL_ADDRESS);
+  }
+
   @Test
   public void inputConnection_textInputTypeMultilineAndSuggestionsDisabled() {
     // Regression test for https://github.com/flutter/flutter/issues/71679.

engine/src/flutter/shell/platform/darwin/ios/framework/Source/FlutterTextInputPlugin.mm

@@ -143,6 +143,9 @@ static UIKeyboardType ToUIKeyboardType(NSDictionary* type) {
   if ([inputType isEqualToString:@"TextInputType.webSearch"]) {
     return UIKeyboardTypeWebSearch;
   }
+  if ([inputType isEqualToString:@"TextInputType.twitter"]) {
+    return UIKeyboardTypeTwitter;
+  }
   return UIKeyboardTypeDefault;
 }
 

engine/src/flutter/shell/platform/darwin/ios/framework/Source/FlutterTextInputPluginTest.mm

@@ -321,6 +321,20 @@ FLUTTER_ASSERT_ARC
   XCTAssertEqual(inputView.keyboardType, UIKeyboardTypeWebSearch);
 }
 
+- (void)testKeyboardTypeTwitter {
+  NSDictionary* config = self.mutableTemplateCopy;
+  [config setValue:@{@"name" : @"TextInputType.twitter"} forKey:@"inputType"];
+  [self setClientId:123 configuration:config];
+
+  // Find all the FlutterTextInputViews we created.
+  NSArray<FlutterTextInputView*>* inputFields = self.installedInputViews;
+
+  FlutterTextInputView* inputView = inputFields[0];
+
+  // Verify keyboardType is set to the value specified in config.
+  XCTAssertEqual(inputView.keyboardType, UIKeyboardTypeTwitter);
+}
+
 - (void)testVisiblePasswordUseAlphanumeric {
   NSDictionary* config = self.mutableTemplateCopy;
   [config setValue:@{@"name" : @"TextInputType.visiblePassword"} forKey:@"inputType"];

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

@@ -203,6 +203,15 @@ class TextInputType {
   /// On Android this is remapped to the [url] keyboard type as it always shows a space bar.
   static const TextInputType webSearch = TextInputType._(11);
 
+  /// Optimized for social media.
+  ///
+  /// Requests a keyboard that includes keys useful for handles and tags.
+  ///
+  /// On iOS, requests a default keyboard with ready access to the "@" and "#" keys.
+  ///
+  /// On Android this is remapped to the [emailAddress] keyboard type as it always shows the "@" key.
+  static const TextInputType twitter = TextInputType._(12);
+
   /// All possible enum values.
   static const List<TextInputType> values = <TextInputType>[
     text,
@@ -217,6 +226,7 @@ class TextInputType {
     streetAddress,
     none,
     webSearch,
+    twitter,
   ];
 
   // Corresponding string name for each of the [values].
@@ -233,6 +243,7 @@ class TextInputType {
     'address',
     'none',
     'webSearch',
+    'twitter',
   ];
 
   // Enum value name, this is what enum.toString() would normally return.

packages/flutter/test/services/text_input_test.dart

@@ -447,6 +447,10 @@ void main() {
         TextInputType.webSearch.toString(),
         'TextInputType(name: TextInputType.webSearch, signed: null, decimal: null)',
       );
+      expect(
+        TextInputType.twitter.toString(),
+        'TextInputType(name: TextInputType.twitter, signed: null, decimal: null)',
+      );
 
       expect(text == number, false);
       expect(number == number2, true);
@@ -476,6 +480,7 @@ void main() {
       expect(TextInputType.streetAddress.index, 9);
       expect(TextInputType.none.index, 10);
       expect(TextInputType.webSearch.index, 11);
+      expect(TextInputType.twitter.index, 12);
 
       expect(
         TextEditingValue.empty.toString(),