Convert garden-o-matic guts over to promises where appropriate

Tools/GardeningServer/scripts/svn-log_unittests.js

 /*
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 168 matching lines @@
     var simulator = new NetworkSimulator();
     simulator.xml = function(url)
     {
         equals(url, 'http://blink.lc/blink/atom');
         var parser = new DOMParser();
         var responseDOM = parser.parseFromString(kExampleCommitDataXML, "application/xml");
         return Promise.resolve(responseDOM);
     };
 
     simulator.runTest(function() {
-        trac.recentCommitData('trunk', 10, function(commitDataList) {
+        return trac.recentCommitData('trunk', 10).then(function(commitDataList) {
             $.each(commitDataList, function(index, commitData) {
                 // Including the entire message makes the deepEqual below to unwieldy.
                 delete commitData.message;
             });
             deepEqual(commitDataList, kExampleCommitDataList);
         });
     }).then(start);
 });
 
 })();