code: function Context(opt_configureForTesting) {
    var closure = this.closure = vm.createContext({
      console: console,
      setTimeout: setTimeout,
      setInterval: setInterval,
      clearTimeout: clearTimeout,
      clearInterval: clearInterval,
      process: process,
      require: require,
      Buffer: Buffer,
      Error: Error,
      CLOSURE_BASE_PATH: path.dirname(CLOSURE_BASE_FILE_PATH) + '/',
      CLOSURE_IMPORT_SCRIPT: function(src) {
        loadScript(src);
        return true;
      },
      CLOSURE_NO_DEPS: !isDevMode(),
      goog: {}
    });
    closure.window = closure.top = closure;
  
    if (opt_configureForTesting) {
      closure.document = {
        body: {},
        createElement: function() { return {}; },
        getElementsByTagName: function() { return []; }
      };
      closure.document.body.ownerDocument = closure.document;
    }
  
    loadScript(CLOSURE_BASE_FILE_PATH);
    loadScript(DEPS_FILE_PATH);
  
    /**
     * Synchronously loads a script into the protected Closure context.
     * @param {string} src Path to the file to load.
     */
    function loadScript(src) {
      src = path.normalize(src);
      var contents = fs.readFileSync(src, 'utf8');
      vm.runInContext(contents, closure, src);
    }
  }
docs: Maintains a unique context for Closure library-based code.
  @param {boolean=} opt_configureForTesting Whether to configure a fake DOM
  for Closure-testing code that (incorrectly) assumes a DOM is always
  present.
  @constructor