Merge CoreTypes and CoreClasses into CommonElements.

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 '../core_types.dart' show CommonElements;
 import '../elements/elements.dart'
     show
         AbstractFieldElement,
         ClassElement,
         ConstructorElement,
         Element,
         EnumClassElement,
-        FieldElement,
         FunctionElement,
         LibraryElement,
         MemberElement,
         MethodElement,
         Name,
         PublicName;
 import '../library_loader.dart' show LoadedLibraries;
 import '../universe/call_structure.dart' show CallStructure;
 import '../universe/selector.dart' show Selector;
 import 'js_backend.dart';
@@ skipping 25 matching lines @@
   final Compiler compiler;
 
   Element cachedCheckConcurrentModificationError;
 
   BackendHelpers(this.compiler);
 
   JavaScriptBackend get backend => compiler.backend;
 
   Resolution get resolution => backend.resolution;
 
-  CoreClasses get coreClasses => compiler.coreClasses;
+  CommonElements get commonElements => compiler.commonElements;
 
   DiagnosticReporter get reporter => compiler.reporter;
 
   MethodElement assertTest;
   MethodElement assertThrow;
   MethodElement assertHelper;
 
   LibraryElement jsHelperLibrary;
   LibraryElement asyncLibrary;
   LibraryElement interceptorsLibrary;
@@ skipping 310 matching lines @@
     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, '==');
+    objectEquals = compiler.lookupElementIn(commonElements.objectClass, '==');
   }
 
   ConstructorElement _mapLiteralConstructor;
   ConstructorElement _mapLiteralConstructorEmpty;
   Element _mapLiteralUntypedMaker;
   Element _mapLiteralUntypedEmptyMaker;
 
   ConstructorElement get mapLiteralConstructor {
     _ensureMapLiteralHelpers();
     return _mapLiteralConstructor;
@@ skipping 397 matching lines @@
   }
 
   ClassElement get stackTraceClass {
     return findHelper('_StackTrace');
   }
 
   MethodElement _objectNoSuchMethod;
 
   MethodElement get objectNoSuchMethod {
     if (_objectNoSuchMethod == null) {
-      _objectNoSuchMethod =
-          coreClasses.objectClass.lookupLocalMember(Identifiers.noSuchMethod_);
+      _objectNoSuchMethod = commonElements.objectClass
+          .lookupLocalMember(Identifiers.noSuchMethod_);
     }
     return _objectNoSuchMethod;
   }
 }