code: function _watchProjectRoot(rootPath) {
          FileSystem.on("change", _fileSystemChange);
          FileSystem.on("rename", _fileSystemRename);
  
          FileSystem.watch(FileSystem.getDirectoryForPath(rootPath), ProjectModel._shouldShowName, ProjectModel.defaultIgnoreGlobs, function (err) {
              if (err === FileSystemError.TOO_MANY_ENTRIES) {
                  if (!_projectWarnedForTooManyFiles) {
                      _showErrorDialog(ERR_TYPE_MAX_FILES);
                      _projectWarnedForTooManyFiles = true;
                  }
              } else if (err) {
                  console.error("Error watching project root: ", rootPath, err);
              }
          });
  
          // Reset allFiles cache
          model._resetCache();
      }
docs: @private
  
  Watches the project for filesystem changes so that the tree can be updated.