Run the later parts of startup as UI thread tasks

content/shell/shell_browser_main.cc

Index: content/shell/shell_browser_main.cc
diff --git a/content/shell/shell_browser_main.cc b/content/shell/shell_browser_main.cc
index d4d65a33d6cc1348ecc3bc49b418dc9ea7cf9de9..140d4aeb8077e01e271c195af8b2729727ba3804 100644
--- a/content/shell/shell_browser_main.cc
+++ b/content/shell/shell_browser_main.cc
@@ -17,6 +17,7 @@
 #include "base/strings/utf_string_conversions.h"
 #include "base/threading/thread_restrictions.h"
 #include "content/public/browser/browser_main_runner.h"
+#include "content/public/common/startup_task_runner.h"
 #include "content/shell/common/shell_switches.h"
 #include "content/shell/common/webkit_test_helpers.h"
 #include "content/shell/shell.h"
@@ -127,8 +128,11 @@ int ShellBrowserMain(
     content::EnsureInitializeForAndroidLayoutTests();
 #endif
   }
+  scoped_refptr<content::StartupTaskRunner> startup_task_runner =
+      make_scoped_refptr(new content::StartupTaskRunner(
+          content::StartupTaskRunner::IMMEDIATE, NULL));
 
-  int exit_code = main_runner->Initialize(parameters);
+  int exit_code = main_runner->Initialize(parameters, startup_task_runner);
   DCHECK_LT(exit_code, 0)
       << "BrowserMainRunner::Initialize failed in ShellBrowserMain";