Fix integration tests in src/chrome and src/extensions so that we can turn on IO thread checks wi...

extensions/browser/guest_view/app_view/app_view_apitest.cc

Index: extensions/browser/guest_view/app_view/app_view_apitest.cc
diff --git a/extensions/browser/guest_view/app_view/app_view_apitest.cc b/extensions/browser/guest_view/app_view/app_view_apitest.cc
index ffa70202ff4f8f9b993d68f19eae00b6a7667b42..276c4b14f5cf25addff5ecdaa29453aabd63334b 100644
--- a/extensions/browser/guest_view/app_view/app_view_apitest.cc
+++ b/extensions/browser/guest_view/app_view/app_view_apitest.cc
@@ -5,6 +5,7 @@
 #include "base/command_line.h"
 #include "base/path_service.h"
 #include "base/strings/stringprintf.h"
+#include "base/threading/thread_restrictions.h"
 #include "components/guest_view/browser/guest_view_manager.h"
 #include "components/guest_view/browser/guest_view_manager_factory.h"
 #include "components/guest_view/browser/test_guest_view_manager.h"
@@ -112,6 +113,7 @@ class AppViewTest : public AppShellTest,
   }
 
   const Extension* LoadApp(const std::string& app_location) {
+    base::ThreadRestrictions::ScopedAllowIO allow_io;
     base::FilePath test_data_dir;
     PathService::Get(DIR_TEST_DATA, &test_data_dir);
     test_data_dir = test_data_dir.AppendASCII(app_location.c_str());