Introduce ClassLike, MemberLike, FieldLike and FunctionLike

pkg/compiler/lib/src/js_backend/backend_helpers.dart

 // Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library dart2js.js_backend.helpers;
 
 import '../common.dart';
 import '../common/names.dart' show Identifiers, Uris;
 import '../common/resolution.dart' show Resolution;
 import '../compiler.dart' show Compiler;
 import '../core_types.dart' show CoreClasses;
 import '../elements/elements.dart'
     show
         AbstractFieldElement,
         ClassElement,
         ConstructorElement,
         Element,
         EnumClassElement,
+        FieldElement,
         FunctionElement,
         LibraryElement,
+        MemberElement,
         MethodElement,
         PublicName;
 import '../library_loader.dart' show LoadedLibraries;
 import '../universe/call_structure.dart' show CallStructure;
 import '../universe/selector.dart' show Selector;
 import 'js_backend.dart';
 
 /// Helper classes and functions for the JavaScript backend.
 class BackendHelpers {
   static final Uri DART_JS_HELPER = new Uri(scheme: 'dart', path: '_js_helper');
@@ skipping 62 matching lines @@
   ClassElement jsMutableIndexableClass;
 
   ClassElement jsMutableArrayClass;
   ClassElement jsFixedArrayClass;
   ClassElement jsExtendableArrayClass;
   ClassElement jsUnmodifiableArrayClass;
   ClassElement jsPositiveIntClass;
   ClassElement jsUInt32Class;
   ClassElement jsUInt31Class;
 
-  Element jsIndexableLength;
+  MemberElement jsIndexableLength;
   Element jsArrayTypedConstructor;
-  Element jsArrayRemoveLast;
-  Element jsArrayAdd;
-  Element jsStringSplit;
+  MethodElement jsArrayRemoveLast;
+  MethodElement jsArrayAdd;
+  MethodElement jsStringSplit;
   Element jsStringToString;
   Element jsStringOperatorAdd;
   Element objectEquals;
 
   ClassElement typeLiteralClass;
   ClassElement mapLiteralClass;
   ClassElement constMapLiteralClass;
   ClassElement typeVariableClass;
   ConstructorElement mapLiteralConstructor;
   ConstructorElement mapLiteralConstructorEmpty;
@@ skipping 241 matching lines @@
       jsFixedArrayClass.ensureResolved(resolution);
     }
     if (jsExtendableArrayClass != null) {
       jsExtendableArrayClass.ensureResolved(resolution);
     }
     if (jsUnmodifiableArrayClass != null) {
       jsUnmodifiableArrayClass.ensureResolved(resolution);
     }
 
     jsIndexableClass.ensureResolved(resolution);
-    jsIndexableLength = compiler.lookupElementIn(jsIndexableClass, 'length');
-    if (jsIndexableLength != null && jsIndexableLength.isAbstractField) {
-      AbstractFieldElement element = jsIndexableLength;
+    Element jsIndexableLengthElement =
+        compiler.lookupElementIn(jsIndexableClass, 'length');
+    if (jsIndexableLengthElement != null &&
+        jsIndexableLengthElement.isAbstractField) {
+      AbstractFieldElement element = jsIndexableLengthElement;
       jsIndexableLength = element.getter;
+    } else {
+      jsIndexableLength = jsIndexableLengthElement;
     }
 
     jsArrayClass.ensureResolved(resolution);
     jsArrayTypedConstructor = compiler.lookupElementIn(jsArrayClass, 'typed');
     jsArrayRemoveLast = compiler.lookupElementIn(jsArrayClass, 'removeLast');
     jsArrayAdd = compiler.lookupElementIn(jsArrayClass, 'add');
 
     jsStringClass.ensureResolved(resolution);
     jsStringSplit = compiler.lookupElementIn(jsStringClass, 'split');
     jsStringOperatorAdd = compiler.lookupElementIn(jsStringClass, '+');
     jsStringToString = compiler.lookupElementIn(jsStringClass, 'toString');
 
     objectEquals = compiler.lookupElementIn(coreClasses.objectClass, '==');
   }
 
   Element get badMain {
     return findHelper('badMain');
   }
 
   Element get missingMain {
     return findHelper('missingMain');
   }
 
   Element get mainHasTooManyParameters {
     return findHelper('mainHasTooManyParameters');
   }
 
-  Element get loadLibraryWrapper {
+  MethodElement get loadLibraryWrapper {
     return findHelper("_loadLibraryWrapper");
   }
 
   Element get boolConversionCheck {
     return findHelper('boolConversionCheck');
   }
 
   Element get consoleTraceHelper {
     return findHelper('consoleTraceHelper');
   }
@@ skipping 301 matching lines @@
   MethodElement _objectNoSuchMethod;
 
   MethodElement get objectNoSuchMethod {
     if (_objectNoSuchMethod == null) {
       _objectNoSuchMethod =
           coreClasses.objectClass.lookupLocalMember(Identifiers.noSuchMethod_);
     }
     return _objectNoSuchMethod;
   }
 }