Issue 26764. Insert required imports in the correct sorting order.

pkg/analysis_server/test/services/correction/assist_test.dart

Index: pkg/analysis_server/test/services/correction/assist_test.dart
diff --git a/pkg/analysis_server/test/services/correction/assist_test.dart b/pkg/analysis_server/test/services/correction/assist_test.dart
index 5c84d352885c1f3b5fab087751562723121bd129..680de778f1ecabab5fce7bb49bfa5d168f03475a 100644
--- a/pkg/analysis_server/test/services/correction/assist_test.dart
+++ b/pkg/analysis_server/test/services/correction/assist_test.dart
@@ -326,8 +326,8 @@ main() {
         'future in',
         DartAssistKind.ADD_TYPE_ANNOTATION,
         '''
-import 'my_lib.dart';
 import 'dart:async';
+import 'my_lib.dart';
 main() {
   for (Future<int> future in getFutures()) {
   }
@@ -466,8 +466,8 @@ main() {
         'v =',
         DartAssistKind.ADD_TYPE_ANNOTATION,
         '''
-import 'my_lib.dart';
 import 'dart:async';
+import 'my_lib.dart';
 main() {
   Future<int> v = getFutureInt();
 }
@@ -515,8 +515,8 @@ main() {
           resultCode,
           '''
 library my_app;
-import 'my_lib.dart';
 import 'dart:async';
+import 'my_lib.dart';
 part 'test.dart';
 ''');
     }
@@ -556,8 +556,8 @@ main() {
         'v =',
         DartAssistKind.ADD_TYPE_ANNOTATION,
         '''
-import 'ccc/lib_b.dart';
 import 'aa/bbb/lib_a.dart';
+import 'ccc/lib_b.dart';
 main() {
   MyClass v = newMyClass();
 }