Use failedAt in more places

pkg/compiler/lib/src/kernel/element_map.dart

 // Copyright (c) 2017, 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.
 
 import 'package:kernel/ast.dart' as ir;
 
 import '../common.dart';
 import '../common/names.dart';
 import '../constants/constructors.dart';
 import '../constants/expressions.dart';
@@ skipping 487 matching lines @@
             return function;
           }
         }
         // If [member] is not a valid `noSuchMethod` the target is
         // `Object.superNoSuchMethod`.
         break;
       }
     }
     FunctionEntity function = elementEnvironment.lookupClassMember(
         commonElements.objectClass, Identifiers.noSuchMethod_);
-    assert(invariant(cls, function != null,
-        message: "No super noSuchMethod found for class $cls."));
+    assert(function != null,
+        failedAt(cls, "No super noSuchMethod found for class $cls."));
     return function;
   }
 }
 
 /// Visitor that converts string literals and concatenations of string literals
 /// into the string value.
 class Stringifier extends ir.ExpressionVisitor<String> {
   @override
   String visitStringLiteral(ir.StringLiteral node) => node.value;
 
@@ skipping 407 matching lines @@
   TypeMask getInferredTypeOf(MemberEntity member);
 
   /// Returns the inferred type of a dynamic [selector] access on a receiver of
   /// type [mask].
   TypeMask selectorTypeOf(Selector selector, TypeMask mask);
 
   /// Returns the returned type annotation in the [nativeBehavior].
   TypeMask typeFromNativeBehavior(
       native.NativeBehavior nativeBehavior, ClosedWorld closedWorld);
 }