fix assert with message

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

 // Copyright (c) 2012, 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.members;
 
 import '../common.dart';
 import '../common/names.dart' show Selectors;
 import '../common/resolution.dart' show Resolution;
 import '../compile_time_constants.dart';
@@ skipping 446 matching lines @@
             resolver.constantCompiler.compileConstant(parameter);
       });
     });
     registry.registerCheckedModeCheck(functionSignature.returnType);
     functionSignature.forEachParameter((ParameterElement element) {
       registry.registerCheckedModeCheck(element.type);
     });
   }
 
   ResolutionResult visitAssert(Assert node) {
-    if (!options.enableAssertMessage) {
-      if (node.hasMessage) {
-        reporter.reportErrorMessage(
-            node, MessageKind.EXPERIMENTAL_ASSERT_MESSAGE);
-      }
-    }
     // TODO(sra): We could completely ignore the assert in production mode if we
     // didn't need it to be resolved for type checking.
     registry.registerFeature(
         node.hasMessage ? Feature.ASSERT_WITH_MESSAGE : Feature.ASSERT);
     visit(node.condition);
     visit(node.message);
     return const NoneResult();
   }
 
   ResolutionResult visitCascade(Cascade node) {
@@ skipping 4264 matching lines @@
     }
     return const NoneResult();
   }
 }
 
 /// Looks up [name] in [scope] and unwraps the result.
 Element lookupInScope(
     DiagnosticReporter reporter, Node node, Scope scope, String name) {
   return Elements.unwrap(scope.lookup(name), reporter, node);
 }