Fix chromedriver test extensions to use manifest version 2 and not inline

chrome/test/webdriver/test/infobar_browser_action_extension/bg.html

Index: chrome/test/webdriver/test/infobar_browser_action_extension/bg.html
diff --git a/chrome/test/webdriver/test/infobar_browser_action_extension/bg.html b/chrome/test/webdriver/test/infobar_browser_action_extension/bg.html
index 20cea3cb96aa4297592f9da903d75cce84f4cb36..379d61e9ea7a3643623978cc1bcae5f8cf785541 100644
--- a/chrome/test/webdriver/test/infobar_browser_action_extension/bg.html
+++ b/chrome/test/webdriver/test/infobar_browser_action_extension/bg.html
@@ -1,18 +1 @@
-<script>
-  var g_infobarReady = false;
-  var g_callback = null;
-  function waitForInfobar(callback) {
-    if (g_infobarReady)
-      callback();
-    g_callback = callback;
-  }
-
-  chrome.tabs.create({'url': 'view_checks.html'}, function(tab) {
-    chrome.experimental.infobars.show(
-        {'tabId': tab.id, 'path': 'view_checks.html'}, function() {
-      g_infobarReady = true;
-      if (g_callback)
-        g_callback();
-    });
-  });
-</script>
+<script src='bg.js'></script>