Don't print clock updates between prints.

lib/src/runner/reporter/compact.dart

 // Copyright (c) 2015, 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 test.runner.reporter.compact;
 
 import 'dart:async';
 import 'dart:io';
 import 'dart:isolate';
 
@@ skipping 284 matching lines @@
   /// [message] goes after the progress report, and may be truncated to fit the
   /// entire line within [_lineLength]. If [color] is passed, it's used as the
   /// color for [message].
   bool _progressLine(String message, {String color, bool truncate: true}) {
     var elapsed = _stopwatch.elapsed.inSeconds;
 
     // Print nothing if nothing has changed since the last progress line.
     if (_engine.passed.length == _lastProgressPassed &&
         _engine.skipped.length == _lastProgressSkipped &&
         _engine.failed.length == _lastProgressFailed &&
-        elapsed == _lastProgressElapsed &&
         message == _lastProgressMessage &&
-        truncate == _lastProgressTruncated) {
+        // Don't re-print just because the message became re-truncated, because
+        // that doesn't add information.
+        (truncate || !_lastProgressTruncated) &&
+        // If we printed a newline, that means the last line *wasn't* a progress
+        // line. In that case, we don't want to print a new progress line just
+        // because the elapsed time changed.
+        (_printedNewline || elapsed == _lastProgressElapsed)) {
       return false;
     }
 
     _lastProgressPassed = _engine.passed.length;
     _lastProgressSkipped = _engine.skipped.length;
     _lastProgressFailed = _engine.failed.length;
     _lastProgressElapsed = elapsed;
     _lastProgressMessage = message;
     _lastProgressTruncated = truncate;
 
@@ skipping 60 matching lines @@
 
     if (_printPlatform && liveTest.suite.platform != null) {
       name = "[${liveTest.suite.platform.name}] $name";
     }
 
     if (liveTest.suite is LoadSuite) name = "$_bold$_gray$name$_noColor";
 
     return name;
   }
 }