code: function getFilesInDirectory(entry, reader, accumEntries, existingPromise) {
          var promise = existingPromise || new qq.Promise(),
              dirReader = reader || entry.createReader();
  
          dirReader.readEntries(
              function readSuccess(entries) {
                  var newEntries = accumEntries ? accumEntries.concat(entries) : entries;
  
                  if (entries.length) {
                      setTimeout(function() { // prevent stack overflow, however unlikely
                          getFilesInDirectory(entry, dirReader, newEntries, promise);
                      }, 0);
                  }
                  else {
                      promise.success(newEntries);
                  }
              },
  
              promise.failure
          );
  
          return promise;
      }
docs: Promissory.  Guaranteed to read all files in the root of the passed directory.