Don't double-print skipped tests in the expanded reporter.

CHANGELOG.md

 ## 0.12.4
 
 * Add a `--pause-after-load` flag that pauses the test runner after each suite
   is loaded so that breakpoints and other debugging annotations can be added.
   Currently this is only supported on browsers.
 
 * Add a `Timeout.none` value indicating that a test should never time out.
 
 * The `dart-vm` platform selector variable is now `true` for Dartium and content
   shell.
 
 * The compact reporter no longer prints status lines that only update the clock
   if they would get in the way of messages or errors from a test.
 
+* The expanded reporter no longer double-prints the descriptions of skipped
+  tests.
+
 ## 0.12.3+9
 
 * Widen the constraint on `analyzer` to include `0.26.0`.
 
 ## 0.12.3+8
 
 * Fix an uncaught error that could crop up when killing the test runner process
   at the wrong time.
 
 ## 0.12.3+7
@@ skipping 234 matching lines @@
 * **NEW!** `expectAsyncUntil` replaces the now deprecated `expectAsyncUntil0`,
     `expectAsyncUntil1` and `expectAsyncUntil2`
 * `TestCase`:
     * Removed properties: `setUp`, `tearDown`, `testFunction`
     * `enabled` is now get-only
     * Removed methods: `pass`, `fail`, `error`
 * `interactive_html_config.dart` has been removed.
 * `runTests`, `tearDown`, `setUp`, `test`, `group`, `solo_test`, and
   `solo_group` now throw a `StateError` if called while tests are running.
 * `rerunTests` has been removed.