lib/qx/tool/compiler/resources/Manager.js
function(callback) {
      log.debug("saving resource manager database");
      return qx.tool.compiler.utils.Json.saveJsonAsync(this.__dbFilename, this.__db);
    }
function(callback) {
      log.debug("saving resource manager database");
      return qx.tool.compiler.utils.Json.saveJsonAsync(this.__dbFilename, this.__db);
    }
Saves the database

@param callback
@async