Adding `content_security_policy` to a few sample extensions.

chrome/common/extensions/docs/examples/api/contentSettings/popup.js

+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+var incognito;
+var url;
+
+function settingChanged() {
+  var type = this.id;
+  var setting = this.value;
+  var pattern = /^file:/.test(url) ? url : url.replace(/\/[^\/]*?$/, '/*');
+  console.log(type+' setting for '+pattern+': '+setting);
+  chrome.contentSettings[type].set({
+        'primaryPattern': pattern,
+        'setting': setting,
+        'scope': (incognito ? 'incognito_session_only' : 'regular')
+      });
+}
+
+document.addEventListener('DOMContentLoaded', function () {
+  chrome.tabs.getSelected(undefined, function(tab) {
+    incognito = tab.incognito;
+    url = tab.url;
+    var types = ['cookies', 'images', 'javascript', 'plugins', 'popups',
+                 'notifications'];
+    types.forEach(function(type) {
+      chrome.contentSettings[type].get({
+            'primaryUrl': url,
+            'incognito': incognito
+          },
+          function(details) {
+            document.getElementById(type).value = details.setting;
+          });
+    });
+  });
+
+  var selects = document.querySelectorAll('select');
+  for (var i = 0; i < selects.length; i++) {
+    selects[i].addEventListener('change', settingChanged);
+  }
+});
+