Remove "unnecessary" imports in material (#75005)

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

@@ -4,7 +4,6 @@
 
 import 'package:flutter/gestures.dart';
 import 'package:flutter/rendering.dart';
-import 'package:flutter/services.dart';
 import 'package:flutter/widgets.dart';
 
 import 'button.dart';

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

@@ -3,7 +3,6 @@
 // found in the LICENSE file.
 
 import 'package:flutter/foundation.dart';
-import 'package:flutter/rendering.dart';
 import 'package:flutter/widgets.dart';
 
 import 'tabs.dart';

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

@@ -4,11 +4,9 @@
 
 import 'dart:ui' as ui show BoxHeightStyle, BoxWidthStyle;
 
-import 'package:characters/characters.dart';
 import 'package:flutter/cupertino.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/services.dart';
-import 'package:flutter/widgets.dart';
 import 'package:flutter/foundation.dart';
 import 'package:flutter/gestures.dart';
 

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

@@ -5,8 +5,6 @@
 import 'dart:math' as math;
 
 import 'package:flutter/rendering.dart';
-import 'package:flutter/scheduler.dart';
-import 'package:flutter/services.dart';
 import 'package:flutter/widgets.dart';
 
 import 'debug.dart';

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

@@ -4,7 +4,6 @@
 
 import 'package:flutter/cupertino.dart';
 import 'package:flutter/foundation.dart';
-import 'package:flutter/widgets.dart';
 
 import 'material_localizations.dart';
 import 'theme_data.dart';

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

@@ -6,8 +6,6 @@ import 'dart:ui' show Color, hashList, lerpDouble;
 
 import 'package:flutter/cupertino.dart';
 import 'package:flutter/foundation.dart';
-import 'package:flutter/services.dart';
-import 'package:flutter/widgets.dart';
 
 import 'app_bar_theme.dart';
 import 'banner_theme.dart';

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

@@ -2,8 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import 'dart:ui' show hashValues;
-
 import 'package:flutter/widgets.dart';
 
 import 'debug.dart';

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

@@ -11,7 +11,6 @@ import 'package:flutter/widgets.dart';
 import 'colors.dart';
 import 'feedback.dart';
 import 'theme.dart';
-import 'theme_data.dart';
 import 'tooltip_theme.dart';
 
 /// A material design tooltip.

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

@@ -5,7 +5,6 @@
 import 'dart:math' as math;
 
 import 'package:flutter/widgets.dart';
-import 'package:flutter/foundation.dart';
 
 import 'colors.dart';
 import 'debug.dart';