title: Background scripts load order
body: <p>I'm observing something odd. I have a few background scripts, well actually a lot - like 18</p>
  
  <pre><code>....
  "background": {
    "scripts": [
      "scripts/namespace.js",
      "scripts/frameworks/honeybadger.js",
      "scripts/frameworks/underscore.js",
      "scripts/frameworks/mixin.js",
      "scripts/frameworks/analytics.js",
      "scripts/modules/worker.js",
      "scripts/modules/i18n.js",
      "scripts/modules/url.js",
      "scripts/trackers/error_tracker.js",
      "scripts/trackers/analytics_tracker.js",
      "scripts/lib/page_context_menu.js",
      "scripts/lib/selection_context_menu.js",
      "scripts/lib/omnibox.js",
      "scripts/lib/sync_store.js",
      "scripts/lib/local_store.js",
      "scripts/lib/example_tags.js",
      "scripts/persistence/tag.js",
      "scripts/init/tag_feature.js",
      "scripts/initialize_background.js"
    ],
    "persistent": false
  }, 
  ....
  </code></pre>
  
  <p>I have HoneyBadger error tracking and I'm seeing errors related to load order. The last script, <code>initialize_background.js</code> is meant to be the starting place. Yet I'm seeing errors like:</p>
  
  <ul>
  <li>Uncaught ReferenceError: _ is not defined (third script loaded)</li>
  <li>Uncaught ReferenceError: _qag is not defined (fifth script loaded)</li>
  </ul>
  
  <p>Has this happened to anyone before? Can the scripts array be trusted to load scripts in order? Should note that I cannot reproduce this. </p>