Add support for assert statements with messages to the analyzer.

pkg/analyzer/test/generated/compile_time_error_code_test.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 engine.compile_time_error_code_test;
 
 import 'package:analyzer/src/generated/error.dart';
 import 'package:analyzer/src/generated/parser.dart' show ParserErrorCode;
 import 'package:analyzer/src/generated/source_io.dart';
 
@@ skipping 204 matching lines @@
     addNamedSource(
         "/lib2.dart",
         r'''
 library lib2;
 class N {}''');
     computeLibrarySourceErrors(source);
     assertErrors(source, [CompileTimeErrorCode.AMBIGUOUS_EXPORT]);
     verify([source]);
   }
 
+  void test_assertWithExtraArgument() {
+    // TODO(paulberry): once DEP 37 is turned on by default, this test should
+    // be removed.
+    Source source = addSource('''
+f(bool x) {
+  assert(x, 'foo');
+}
+''');
+    computeLibrarySourceErrors(source);
+    assertErrors(source, [CompileTimeErrorCode.EXTRA_ARGUMENT_TO_ASSERT]);
+    verify([source]);
+  }
+
   void test_async_used_as_identifier_in_annotation() {
     Source source = addSource('''
 const int async = 0;
 f() async {
   g(@async x) {}
   g(0);
 }
 ''');
     computeLibrarySourceErrors(source);
     assertErrors(source, [ParserErrorCode.ASYNC_KEYWORD_USED_AS_IDENTIFIER]);
@@ skipping 5944 matching lines @@
         source, [CompileTimeErrorCode.WRONG_NUMBER_OF_PARAMETERS_FOR_OPERATOR]);
     verify([source]);
     reset();
   }
 
   void _check_wrongNumberOfParametersForOperator1(String name) {
     _check_wrongNumberOfParametersForOperator(name, "");
     _check_wrongNumberOfParametersForOperator(name, "a, b");
   }
 }