MD Settings: Fix remaining tests that fail in Vulcanized mode.

chrome/test/data/webui/settings/search_settings_test.js

Index: chrome/test/data/webui/settings/search_settings_test.js
diff --git a/chrome/test/data/webui/settings/search_settings_test.js b/chrome/test/data/webui/settings/search_settings_test.js
index 1884e9c5d6be73cbad1bd97282875f9fae79e205..9653441b2605fad96299beb66b9ef9922faf5c6b 100644
--- a/chrome/test/data/webui/settings/search_settings_test.js
+++ b/chrome/test/data/webui/settings/search_settings_test.js
@@ -7,8 +7,12 @@ cr.define('settings_test', function() {
   suite('SearchSettingsTest', function() {
     var searchManager;
 
+    // Don't import script if already imported (happens in Vulcanized mode).
     suiteSetup(function() {
-      return PolymerTest.loadScript('chrome://md-settings/search_settings.js');
+      if (!window.settings || !settings.getSearchManager) {
+        return PolymerTest.loadScript(
+            'chrome://md-settings/search_settings.js');
+      }
     });
 
     setup(function() {