Error adding extension to google chrome

So I'm getting started in on making chrome extensions and I find it confusing to understand JSON because I don't have too much experience with it. I'm trying to connect my JavaScript to the extension but it says it's not secure. Can somebody tell me whats wrong with my code?

HTML

    <html>

<head>
  <link rel="stylesheet" href="style.css">
  <script type="text/javascript" src="script.js"></script>
  <title>Miguel Betancourt</title>
</head>

<body>
  <div class="extenContainer">
    <h3 class="logo"></h3>
  </div>

  <div class="counter">
    <button onclick="plus()">test</button>
    <a href="#"<div class="buttonL" onclick="minus()"></div></a>
        <p id="number">0</p>
    <a href=""<div class="buttonR" onclick="plus()"></div></a>
  </div>

</body>

</html>

JavaScript

var add = (function () {
    var counter = 0;
    return function () {return counter += 1;}
})();

function myFunction(){
    document.getElementById("demo").innerHTML = add();
}

JSON

{
  "manifest_version": 2,

  "name": "Poop Counter",
  "description": "How much have you pooped?",
  "version": "1.0",

  "browser_action": {
    "default_icon":"icon.png",
    "default_popup": "popup.html"

  },

  "permissions": [
    "activeTab",
    "https://ajax.googleapis.com/"
  ],

  "content_scripts":[
    {
      "matches": ["http://www.google.com/*"],
      "css": ["style.css"],
      "js":  ["script.js"],
},
]