Block tabs.executeScript() from executing until user grants permission

chrome/test/data/extensions/active_script/inject_scripts_all_hosts/background.js

 // Copyright 2014 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.
 
-chrome.tabs.onUpdated.addListener(function(tabId) {
-  chrome.tabs.executeScript(
-      tabId,
-      { code: 'chrome.test.sendMessage("inject_scripts_all_hosts");' });
-});
+var listener = function(tabId) {
+  chrome.tabs.onUpdated.removeListener(listener);
+  chrome.tabs.executeScript(tabId, {
+    code: "chrome.test.sendMessage('inject succeeded');"
+  });
+  chrome.test.sendMessage('inject attempted');
+};
+
+chrome.tabs.onUpdated.addListener(listener);