Issue 12158. Report error when user code uses 'native' clause.

tests/language/language_analyzer.status

 # 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.
 
 [ $compiler == dartanalyzer ]
 
 # Runtime negative test. No static errors or warnings.
 closure_call_wrong_argument_count_negative_test: skip
 
 illegal_invocation_test/01: fail # Issue: 11892
@@ skipping 263 matching lines @@
 # test issue 11965, 'source' is not built-in identifier anymore
 pseudo_kw_illegal_test/14: fail
 
 # test issue 12156, fails only at runtime
 static_call_wrong_argument_count_negative_test: fail
 
 # test issue 12157, uninitializer instance variable is warning, so not negative test
 static_final_field_negative_test: fail
 constructor2_negative_test: fail
 
-# test issue 12158, 'native' is not in spec, so analyzer does not generate compile-time error
-syntax_test/28: fail
-syntax_test/29: fail
-syntax_test/30: fail
-syntax_test/31: fail
-syntax_test/32: fail
-syntax_test/33: fail
-
 # test issue 12159, print(exception.message_); causes static warning, not an error
 throw7_negative_test: fail
 
 # test issue 12160, not annotated warnings for type variables from static member
 type_parameter_test/none: fail
 # test issue 12161, type variable in static, malformed type, static warning
 type_variable_static_context_negative_test: fail
 
 # test issue 12162, 'a' has dynamic type, so it statically it is assignable to anything
 type_variable_bounds2_test/00: fail
@@ skipping 31 matching lines @@
 factory_redirection_test/09: fail
 factory_redirection_test/10: fail
 factory_redirection_test/11: fail
 factory_redirection_test/12: fail
 factory_redirection_test/13: fail
 factory_redirection_test/14: fail
 getters_setters2_test/03: fail
 type_variable_bounds3_test/00: fail
 type_variable_bounds2_test/05: fail