Revert of Remove the is_loading_ field from WebContentsImpl

chrome/browser/extensions/extension_resource_request_policy_apitest.cc

Index: chrome/browser/extensions/extension_resource_request_policy_apitest.cc
diff --git a/chrome/browser/extensions/extension_resource_request_policy_apitest.cc b/chrome/browser/extensions/extension_resource_request_policy_apitest.cc
index bb5a30a0c2bb0d04e37cd990cbd7f1b56179abc2..348f95839fb7eb3d7449073cb56ff3ab3955847d 100644
--- a/chrome/browser/extensions/extension_resource_request_policy_apitest.cc
+++ b/chrome/browser/extensions/extension_resource_request_policy_apitest.cc
@@ -227,7 +227,7 @@
       "web_accessible/accessible_history_navigation.html"));
   ui_test_utils::NavigateToURL(browser(), newtab_page);
   ui_test_utils::NavigateToURLBlockUntilNavigationsComplete(
-      browser(), accessible_newtab_override, 1);
+      browser(), accessible_newtab_override, 2);
   ASSERT_TRUE(content::ExecuteScriptAndExtractString(
       browser()->tab_strip_model()->GetActiveWebContents(),
       "window.domAutomationController.send(document.title)",
@@ -246,8 +246,8 @@
   GURL accessible_linked_resource(embedded_test_server()->GetURL(
       "/extensions/api_test/extension_resource_request_policy/"
       "web_accessible/accessible_link_resource.html"));
-  ui_test_utils::NavigateToURLBlockUntilNavigationsComplete(
-      browser(), accessible_linked_resource, 1);
+  ui_test_utils::NavigateToURLBlockUntilNavigationsComplete(browser(),
+      accessible_linked_resource, 2);
   ASSERT_TRUE(content::ExecuteScriptAndExtractString(
       browser()->tab_strip_model()->GetActiveWebContents(),
       "window.domAutomationController.send(document.URL)",