Fix some type warnings in the test scripts, that show up when using the editor.

tools/testing/dart/test_progress.dart

 // 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.
 
 #library("test_progress");
 
 #import("dart:io");
 #import("dart:builtin");
 #import("test_runner.dart");
 #import("test_suite.dart");
@@ skipping 68 matching lines @@
     }
   }
 
   void allDone() {
     _printFailureSummary();
     _printStatus();
     _printTimingInformation();
     exit(_failedTests > 0 ? 1 : 0);
   }
 
-  abstract _printStartProgress(TestCase test);
-  abstract _printDoneProgress(TestCase test);
+  void _printStartProgress(TestCase test) {}
+  void _printDoneProgress(TestCase test) {}
 
   String _pad(String s, int length) {
     StringBuffer buffer = new StringBuffer();
     for (int i = s.length; i < length; i++) {
       buffer.add(' ');
     }
     buffer.add(s);
     return buffer.toString();
   }
 
@@ skipping 250 matching lines @@
     var status = 'pass';
     if (test.output.unexpectedOutput) {
       status = 'fail';
     }
     var percent = ((_completedTests() / _foundTests) * 100).toInt().toString();
     print('Done ${test.configurationString} ${test.displayName}: $status');
     print('@@@STEP_CLEAR@@@');
     print('@@@STEP_TEXT@ $percent% +$_passedTests -$_failedTests @@@');
   }
 }