Use failedAt in more places

pkg/compiler/lib/src/resolution/registry.dart

 // Copyright (c) 2014, 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.resolution.registry;
 
 import '../common.dart';
 import '../common/backend_api.dart' show ForeignResolver, NativeRegistry;
 import '../common/resolution.dart' show ResolutionImpact, Target;
 import '../constants/expressions.dart';
@@ skipping 261 matching lines @@
     mapping.undefineLabel(node);
   }
 
   /// Register the target of [node] as reference to [label].
   void useLabel(GotoStatement node, LabelDefinition label) {
     mapping.registerTargetLabel(node, label);
   }
 
   /// Register [node] to be the declaration of [target].
   void defineTarget(Node node, JumpTarget target) {
-    assert(invariant(node, node is Statement || node is SwitchCase,
-        message: "Only statements and switch cases can define targets."));
+    assert(node is Statement || node is SwitchCase,
+        failedAt(node, "Only statements and switch cases can define targets."));
     mapping.defineTarget(node, target);
   }
 
   /// Returns the [JumpTarget] defined by [node].
   JumpTarget getTargetDefinition(Node node) {
-    assert(invariant(node, node is Statement || node is SwitchCase,
-        message: "Only statements and switch cases can define targets."));
+    assert(node is Statement || node is SwitchCase,
+        failedAt(node, "Only statements and switch cases can define targets."));
     return mapping.getTargetDefinition(node);
   }
 
   /// Undefine the target of [node]. This is used to cleanup unused targets.
   void undefineTarget(Node node) {
-    assert(invariant(node, node is Statement || node is SwitchCase,
-        message: "Only statements and switch cases can define targets."));
+    assert(node is Statement || node is SwitchCase,
+        failedAt(node, "Only statements and switch cases can define targets."));
     mapping.undefineTarget(node);
   }
 
   /// Register the target of [node] to be [target].
   void registerTargetOf(GotoStatement node, JumpTarget target) {
     mapping.registerTargetOf(node, target);
   }
 
   //////////////////////////////////////////////////////////////////////////////
   //  Potential access registration.
@@ skipping 129 matching lines @@
   @override
   void registerInstantiatedType(ResolutionInterfaceType type) {
     registry.registerInstantiation(type);
   }
 
   @override
   ResolutionDartType resolveTypeFromString(Node node, String typeName) {
     return visitor.resolveTypeFromString(node, typeName);
   }
 }