Simple browser version of nextTick function

nextTick.js

// https://github.com/kriskowal/q/blob/d373079d3620152e3d60e82f27265a09ee0e81bd/q.js#L101-L248

// Use the fastest possible means to execute a task in a future turn
// of the event loop.

var nextTick = (function () {
  var head = {task: null, tail: null};
  var tail = head;
  var flushing = false;

  function run(task) {
    try {
      task();
    } catch (e) {
      setTimeout(function () {
        throw e;
      }, 0);
    }
  }

  function flush() {
    var task;
    while (head.next) {
      head = head.next;
      task = head.task;
      head.task = null;
      run(task);
    }
    flushing = false;
  }

  nextTick = function (task) {
    tail = tail.next = {
      task: task,
      next: null
    };

    if (!flushing) {
      flushing = true;
      setTimeout(flush, 0);
    }
  };

  return nextTick;
})();