Adding `content_security_policy` to a few sample extensions

chrome/common/extensions/docs/examples/api/webNavigation/basic/background.js

Index: chrome/common/extensions/docs/examples/api/webNavigation/basic/background.js
diff --git a/chrome/common/extensions/docs/examples/api/webNavigation/basic/background.js b/chrome/common/extensions/docs/examples/api/webNavigation/basic/background.js
new file mode 100644
index 0000000000000000000000000000000000000000..09e3699d855897598718cf401b18221094f7519e
--- /dev/null
+++ b/chrome/common/extensions/docs/examples/api/webNavigation/basic/background.js
@@ -0,0 +1,22 @@
+// 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.
+
+/**
+ * @filedescription Initializes the extension's background page.
+ */
+
+var nav = new NavigationCollector();
+
+var eventList = ['onBeforeNavigate', 'onCreatedNavigationTarget',
+    'onCommitted', 'onCompleted', 'onDOMContentLoaded',
+    'onErrorOccurred', 'onReferenceFragmentUpdated'];
+
+eventList.forEach(function(e) {
+  chrome.webNavigation[e].addListener(function(data) {
+    if (typeof data)
+      console.log(chrome.i18n.getMessage('inHandler'), e, data);
+    else
+      console.error(chrome.i18n.getMessage('inHandlerError'), e);
+  });
+});