Move remaining helpers to BackendHelpers

pkg/compiler/lib/src/js_backend/js_interop_analysis.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.
 
 /// Analysis to determine how to generate code for typed JavaScript interop.
 library compiler.src.js_backend.js_interop_analysis;
 
 import '../common/names.dart' show Identifiers;
 import '../compiler.dart' show Compiler;
 import '../diagnostics/messages.dart' show MessageKind;
@@ skipping 12 matching lines @@
         FieldElement,
         FunctionElement,
         LibraryElement,
         MetadataAnnotation;
 
 import '../js/js.dart' as jsAst;
 import '../js/js.dart' show js;
 import '../universe/selector.dart' show Selector;
 import '../universe/universe.dart' show SelectorConstraints;
 
+import 'backend_helpers.dart' show BackendHelpers;
 import 'js_backend.dart' show JavaScriptBackend;
 
 class JsInteropAnalysis {
   final JavaScriptBackend backend;
 
   /// The resolved [FieldElement] for `Js.name`.
   FieldElement nameField;
   bool enabledJsInterop = false;
 
   /// Whether the backend is currently processing the codegen queue.
   bool _inCodegen = false;
 
   JsInteropAnalysis(this.backend);
 
+  BackendHelpers get helpers => backend.helpers;
+
   void onQueueClosed() {
     if (_inCodegen) return;
 
-    if (backend.jsAnnotationClass != null) {
-      nameField = backend.jsAnnotationClass.lookupMember('name');
+    if (helpers.jsAnnotationClass != null) {
+      nameField = helpers.jsAnnotationClass.lookupMember('name');
       backend.compiler.libraryLoader.libraries
           .forEach(processJsInteropAnnotationsInLibrary);
     }
   }
 
   void onCodegenStart() {
     _inCodegen = true;
   }
 
   void processJsInteropAnnotation(Element e) {
     for (MetadataAnnotation annotation in e.implementation.metadata) {
       ConstantValue constant = backend.compiler.constants.getConstantValue(
           annotation.constant);
       if (constant == null || constant is! ConstructedConstantValue) continue;
       ConstructedConstantValue constructedConstant = constant;
-      if (constructedConstant.type.element == backend.jsAnnotationClass) {
+      if (constructedConstant.type.element == helpers.jsAnnotationClass) {
         ConstantValue value = constructedConstant.fields[nameField];
         if (value.isString) {
           StringConstantValue stringValue = value;
           backend.setJsInteropName(
               e, stringValue.primitiveValue.slowToString());
         } else {
           // TODO(jacobr): report a warning if the value is not a String.
           backend.setJsInteropName(e, '');
         }
         enabledJsInterop = true;
         return;
       }
     }
   }
 
   void processJsInteropAnnotationsInLibrary(LibraryElement library) {
     processJsInteropAnnotation(library);
     library.implementation.forEachLocalMember((Element element) {
       processJsInteropAnnotation(element);
       if (!element.isClass || !backend.isJsInterop(element)) return;
 
       ClassElement classElement = element;
 
       if (!classElement
-          .implementsInterface(backend.jsJavaScriptObjectClass)) {
+          .implementsInterface(helpers.jsJavaScriptObjectClass)) {
         backend.reporter.reportErrorMessage(classElement,
             MessageKind.JS_INTEROP_CLASS_CANNOT_EXTEND_DART_CLASS, {
           'cls': classElement.name,
           'superclass': classElement.superclass.name
         });
       }
 
       classElement.forEachMember(
           (ClassElement classElement, Element member) {
         processJsInteropAnnotation(member);
@@ skipping 31 matching lines @@
           var name = backend.namer.invocationName(selector);
           statements.add(js.statement(
               'Function.prototype.# = function(#) { return this(#) }',
               [name, parameters, parameters]));
         }
       });
     });
     return new jsAst.Block(statements);
   }
 }