title: JS include tag not being removed from dom, even though it has been removed from the file
body: <p>I'm building a rails app, and I'm having an issue where i'm getting two confirmation boxes popping up, rather than one when I use :confirm.</p>
  
  <p>I've come to the conclusion that this is a result of <code>rails.js</code> being included twice, once in my layout, and once in <code>application.js</code>. However, when I deleted <code>&lt;%=javascript_include_tag "rails.js"%&gt;</code> from <code>application.html.erb</code>, and do view page source on the app it still shows it being included.</p>
  
  <p>I tried deleting my browser cache, restarting the browser, going in incognito mode, I cleaned my assets pipeline, made sure <code>config.assets.debug = false</code>. Any ideas on how to alleviate this issue? Thanks.</p>
  
  <p>head portion of application.html.erb:</p>
  
  <pre><code>    &lt;head&gt;
         &lt;%= csrf_meta_tag %&gt;
          &lt;meta charset="utf-8"&gt;
          &lt;!-- [if IE]&gt;  &lt;meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1"&gt;&lt;![endif]--&gt;
          &lt;title&gt;Title&lt;/title&gt;
          &lt;meta name="description" content=""&gt;
          &lt;!-- &lt;meta name="viewport" content="width=device-width"&gt; --&gt;
          &lt;meta name="viewport" content="width=device-width, minimum-scale=1.0, maximum-scale=1.0, user-scalable=no"&gt;
  
          &lt;!-- Place favicon.ico and apple-touch-icon.png in the root directory --&gt;
  &lt;%= javascript_include_tag "application" %&gt;
          &lt;%=stylesheet_link_tag("normalize")%&gt;
          &lt;%=stylesheet_link_tag("main")%&gt;
          &lt;%=stylesheet_link_tag("r")%&gt;
          &lt;%=stylesheet_link_tag("webfonts/ss-standard")%&gt;
          &lt;!--link type="text/css" href="css/jquery.jscrollpane.css"--&gt;
  
  
  
  
          &lt;%=javascript_include_tag "vendor/modernizr-2.6.1.min"%&gt;
          &lt;%=javascript_include_tag "//use.typekit.net/rwg2mxn.js"%&gt;      
          &lt;script type="text/javascript"&gt;try{Typekit.load();}catch(e){}&lt;/script&gt;
          &lt;%=javascript_include_tag "jquery.cookie.js"%&gt;
          &lt;!--script type="text/javascript" src="http://platform.linkedin.com/in.js"&gt;
              api_key: YOUR_API_KEY_GOES_HERE
              authorize: true
          &lt;/script--&gt;
          &lt;%=javascript_include_tag "plugins.js"%&gt;
          &lt;%=javascript_include_tag "vendor/jquery.touchSwipe.min"%&gt;
          &lt;!--script src="js/vendor/jquery.mousewheel.js"&gt;&lt;/script&gt;
          &lt;script src="js/vendor/jquery.jscrollpane.min.js"&gt;&lt;/script--&gt;
  
      &lt;%=yield :head%&gt;
  
      &lt;/head&gt;
  </code></pre>
  
  <p>application.js:</p>
  
  <pre><code>// This is a manifest file that'll be compiled into application.js, which will include all the files
  // listed below.
  //
  // Any JavaScript/Coffee file within this directory, lib/assets/javascripts, vendor/assets/javascripts,
  // or vendor/assets/javascripts of plugins, if any, can be referenced here using a relative path.
  //
  // It's not advisable to add code directly here, but if you do, it'll appear at the bottom of the
  // the compiled file.
  //
  // WARNING: THE FIRST BLANK LINE MARKS THE END OF WHAT'S TO BE PROCESSED, ANY BLANK LINE SHOULD
  // GO AFTER THE REQUIRES BELOW.
  //
  //= require jquery
  //= require jquery-fileupload/basic
  //= require jquery-fileupload/vendor/tmpl
  //= require_tree .
  </code></pre>