Convert isX() methods to isX getter.

pkg/analyzer_experimental/test/generated/element_test.dart

 // This code was auto-generated, is not intended to be edited, and is subject to
 // significant change. Please see the README file for more information.
 library engine.element_test;
 import 'dart:collection';
 import 'dart:io';
 import 'package:analyzer_experimental/src/generated/java_core.dart';
 import 'package:analyzer_experimental/src/generated/java_engine.dart';
 import 'package:analyzer_experimental/src/generated/java_engine_io.dart';
 import 'package:analyzer_experimental/src/generated/java_junit.dart';
 import 'package:analyzer_experimental/src/generated/source_io.dart';
@@ skipping 2714 matching lines @@
       });
       _ut.test('test_substitute2_notEqual', () {
         final __test = new FunctionTypeImplTest();
         runJUnitTest(__test, __test.test_substitute2_notEqual);
       });
     });
   }
 }
 class InterfaceTypeImpl_18 extends InterfaceTypeImpl {
   InterfaceTypeImpl_18(ClassElement arg0) : super.con1(arg0);
-  bool isDartCoreFunction() => true;
+  bool get isDartCoreFunction => true;
 }
 main() {
   ElementKindTest.dartSuite();
   FunctionTypeImplTest.dartSuite();
   InterfaceTypeImplTest.dartSuite();
   TypeVariableTypeImplTest.dartSuite();
   ClassElementImplTest.dartSuite();
   ElementLocationImplTest.dartSuite();
   ElementImplTest.dartSuite();
   LibraryElementImplTest.dartSuite();
 }