Introduce convenience methods into generated analysis server classes.

pkg/analysis_server/test/services/refactoring/abstract_rename.dart

Index: pkg/analysis_server/test/services/refactoring/abstract_rename.dart
diff --git a/pkg/analysis_server/test/services/refactoring/abstract_rename.dart b/pkg/analysis_server/test/services/refactoring/abstract_rename.dart
index dd7580da9d445361c7be332456c47cca9380600c..585b9d97279402ec1a9c97d3363b91e2e4f9ce78 100644
--- a/pkg/analysis_server/test/services/refactoring/abstract_rename.dart
+++ b/pkg/analysis_server/test/services/refactoring/abstract_rename.dart
@@ -37,7 +37,7 @@ class RenameRefactoringTest extends RefactoringTest {
     File file = provider.getResource(path);
     Source source = file.createSource();
     String ini = context.getContents(source).data;
-    String actualCode = applySequence(ini, fileEdit.edits);
+    String actualCode = SourceEdit.applySequence(ini, fileEdit.edits);
     expect(actualCode, expectedCode);
   }