Added support for isolate unhandled exceptions.

tests/isolate/isolate.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.
 
 [ $runtime == vm ]
 isolate2_negative_test: Skip  # Need to resolve correct behaviour.
+isolate3_negative_test: Skip  # test depends on isolate error exiting process.
 serialization_test: Skip  # tests dart2js-specific serialization code
 spawn_uri_test: Fail, OK # test uses a ".js" suffix that is bogus on vm.
 compute_this_script_browser_test: Skip # browser specific test
 timer_not_available_test: Fail, OK # only meant to test when there is no way to
                                    # implement timer (currently only in d8)
 timer_isolate_test: Skip # See Issue 4997
+unresolved_ports_negative_test: Skip # See Issue 6839
 
 [ $compiler == none && $runtime == drt ]
 serialization_test: Skip  # tests dart2js-specific serialization code
 spawn_uri_test: Skip # uses a .js extension (not for dartium)
 spawn_uri_negative_test: Skip # ditto
 spawn_uri_vm_test: Skip # not implemented in dartium yet.
 spawn_uri_vm_negative_test: Skip
 timer_isolate_test: Pass, Fail # See Issue 4997
 timer_not_available_test: Fail, OK # only meant to test when there is no way to
                                    # implement timer (currently only in d8)
@@ skipping 38 matching lines @@
 
 [ $runtime == ie9 && ($system == linux || $system == macos) ]
 *: Skip
 
 [ $runtime == safari && ($system == linux || $system == windows) ]
 *: Skip
 
 [ $runtime == opera ]
 multiple_timer_test: Pass, Fail
 isolate2_negative_test: Skip # Timeout.
-unresolved_ports_negative_test: Skip # Timeout.
+unresolved_ports_negative_test: Skip # See Issue 6839
 
 [ $runtime == opera && $system == windows]
 # TODO(efortuna): Investigate.
 timer_test: Fail, Pass
 
 [ $arch == simarm ]
 *: Skip
 
 [ $arch == arm ]
 *: Skip
@@ skipping 18 matching lines @@
 timer_isolate_test: Fail, OK # Needs Timer to run.
 timer_repeat_test: Fail,OK # Needs Timer to run.
 timer_test: Fail,OK # Needs Timer to run.
 
 [ $compiler == dart2js && $runtime == none ]
 *: Fail, Pass # TODO(ahe): Triage these tests.
 
 [ $compiler == dart2dart ]
 # Skip until we stabilize language tests.
 *: Skip