Use failedAt in more places (js_emitter)

pkg/compiler/lib/src/js_emitter/full_emitter/class_emitter.dart

 // Copyright (c) 2013, 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_emitter.full_emitter.class_emitter;
 
 import '../../common.dart';
 import '../../common/names.dart' show Names;
 import '../../elements/resolution_types.dart' show ResolutionDartType;
 import '../../deferred_load.dart' show OutputUnit;
@@ skipping 18 matching lines @@
   ClassStubGenerator get _stubGenerator => new ClassStubGenerator(task.emitter,
       compiler.commonElements, namer, codegenWorldBuilder, closedWorld,
       enableMinification: compiler.options.enableMinification);
 
   /**
    * Documentation wanted -- johnniwinther
    */
   void emitClass(Class cls, ClassBuilder enclosingBuilder, Fragment fragment) {
     ClassElement classElement = cls.element;
 
-    assert(invariant(classElement, classElement.isDeclaration));
+    assert(classElement.isDeclaration, failedAt(classElement));
 
     emitter.needsClassSupport = true;
 
     ClassElement superclass = classElement.superclass;
     jsAst.Name superName;
     if (superclass != null) {
       superName = namer.className(superclass);
     }
 
     if (cls.isMixinApplication) {
@@ skipping 201 matching lines @@
     }
   }
 
   /**
    * Documentation wanted -- johnniwinther
    *
    * Invariant: [classElement] must be a declaration element.
    */
   void emitInstanceMembers(Class cls, ClassBuilder builder) {
     ClassElement classElement = cls.element;
-    assert(invariant(classElement, classElement.isDeclaration));
+    assert(classElement.isDeclaration, failedAt(classElement));
 
     if (cls.onlyForRti || cls.isMixinApplication) return;
 
     // TODO(herhut): This is a no-op. Should it be removed?
     for (Field field in cls.fields) {
       emitter.containerBuilder.addMemberField(field, builder);
     }
 
     for (Method method in cls.methods) {
-      assert(invariant(classElement, method.element.isInstanceMember));
+      assert(method.element.isInstanceMember, failedAt(classElement));
       emitter.containerBuilder.addMemberMethod(method, builder);
     }
 
     if (classElement.isObject && closedWorld.backendUsage.isNoSuchMethodUsed) {
       // Emit the noSuchMethod handlers on the Object prototype now,
       // so that the code in the dynamicFunction helper can find
       // them. Note that this helper is invoked before analyzing the
       // full JS script.
       emitter.nsmEmitter.emitNoSuchMethodHandlers(builder.addProperty);
     }
@@ skipping 99 matching lines @@
       FieldElement member, jsAst.Name accessorName, String memberName) {
     if (!backend.mirrorsData.shouldRetainGetter(member)) return;
     String previousName;
     if (member.isInstanceMember) {
       previousName = emitter.mangledFieldNames
           .putIfAbsent(namer.deriveGetterName(accessorName), () => memberName);
     } else {
       previousName = emitter.mangledGlobalFieldNames
           .putIfAbsent(accessorName, () => memberName);
     }
-    assert(invariant(member, previousName == memberName,
-        message: '$previousName != ${memberName}'));
+    assert(previousName == memberName,
+        failedAt(member, '$previousName != ${memberName}'));
   }
 
   void emitGetterForCSP(FieldElement member, jsAst.Name fieldName,
       jsAst.Name accessorName, ClassBuilder builder) {
     jsAst.Expression function =
         _stubGenerator.generateGetter(member, fieldName);
 
     jsAst.Name getterName = namer.deriveGetterName(accessorName);
     ClassElement cls = member.enclosingClass;
     jsAst.Name className = namer.className(cls);
@@ skipping 39 matching lines @@
     String reflectionName = emitter.getReflectionName(selector, name);
     if (reflectionName != null) {
       var reflectable = js(
           backend.mirrorsData.isMemberAccessibleByReflection(member)
               ? '1'
               : '0');
       builder.addPropertyByName('+$reflectionName', reflectable);
     }
   }
 }