Issue 1606/1108. The 'native' keyword is supposed to only be allowed in core libraries.

tests/language/language.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.
 
 # This directory contains tests that are intended to show the
 # current state of the language.
 
 # In order to maintain maximum test coverage for all builds,
 # please use the following procedure to mark a test
 # failed on architectures other than the one you are working on.
@@ skipping 168 matching lines @@
 PseudoKWIllegalTest/13: Fail # Issue 356
 PseudoKWIllegalTest/14: Fail # Issue 356
 PseudoKWIllegalTest/15: Fail # Issue 356
 PseudoKWIllegalTest/16: Fail # Issue 356
 ScopeNegativeTest: Fail      # Bug 4207538.
 StringEscape1NegativeTest: Fail # Issue 1351.
 StringEscape4NegativeTest: Fail # Issue 1351.
 SuperOperatorTest: Fail      # Bug 4995463.
 Switch7NegativeTest: Fail    # Bug 4208467.
 SwitchLabelTest: Fail        # Bug 4208467.
-SyntaxTest/29: Fail          # Issue 1606
-SyntaxTest/30: Fail          # Issue 1606
-SyntaxTest/31: Fail          # Issue 1108
-SyntaxTest/32: Fail          # Issue 1108
-SyntaxTest/33: Fail # Issue 1108
 ThirdTest: Skip # Seems flaky in dartc after fixing test, was Bug 5339586
 Throw7NegativeTest: Fail     # Bug 4208459.
 
 #
 # Add new dartc annotations above in alphabetical order
 #
 
 # VM or Frog specific tests that should not be run by DartC.
 *VMTest: Skip
 *VMNegativeTest: Skip
@@ skipping 257 matching lines @@
 [ $component == frog && $mode == debug ]
 ConstructorRedirect1NegativeTest: Skip # Undiagnosed infinite loop.
 ConstructorRedirect2NegativeTest: Skip # Undiagnosed infinite loop.
 
 [ $arch == simarm ]
 *: Skip
 
 [ $arch == arm ]
 *: Skip