[MD settings] expand subpages to 100%

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

Index: chrome/test/data/webui/settings/settings_main_test.js
diff --git a/chrome/test/data/webui/settings/settings_main_test.js b/chrome/test/data/webui/settings/settings_main_test.js
index 0e02be927ba144a1da2868a261f40a9dec5f15c9..7d5b2812e249acb737ffeb317cfbe808b15dee23 100644
--- a/chrome/test/data/webui/settings/settings_main_test.js
+++ b/chrome/test/data/webui/settings/settings_main_test.js
@@ -176,7 +176,8 @@ cr.define('settings_main_page', function() {
         assertEquals(
             expectedBasic, page.$$('#basicPage').style.display);
         assertEquals(
-            expectedAdvanced, page.$.advancedPageTemplate.get().style.display);
+            expectedAdvanced,
+            page.$$('#advancedPageTemplate').get().style.display);
       }
 
       // TODO(michaelpg): It would be better not to drill into