Do not spawn a thread in browser/interactive ui tests before spawning sandbox host process

chrome/browser/extensions/api/system_private/system_private_apitest.cc

Index: chrome/browser/extensions/api/system_private/system_private_apitest.cc
diff --git a/chrome/browser/extensions/api/system_private/system_private_apitest.cc b/chrome/browser/extensions/api/system_private/system_private_apitest.cc
index b49b396eb726880904ce8106fc152f058b150821..f24209546a12ebb2d91d1b569d30fb3b520d8db4 100644
--- a/chrome/browser/extensions/api/system_private/system_private_apitest.cc
+++ b/chrome/browser/extensions/api/system_private/system_private_apitest.cc
@@ -37,11 +37,11 @@ class GetUpdateStatusApiTest : public ExtensionApiTest {
     fake_update_engine_client_ = new chromeos::FakeUpdateEngineClient;
     fake_dbus_thread_manager->SetUpdateEngineClient(
         scoped_ptr<UpdateEngineClient>(fake_update_engine_client_));
-    chromeos::DBusThreadManager::InitializeForTesting(fake_dbus_thread_manager);
+    chromeos::DBusThreadManager::SetInstanceForTesting(
+        fake_dbus_thread_manager);
   }
 
   virtual void TearDownInProcessBrowserTestFixture() OVERRIDE {
-    chromeos::DBusThreadManager::Shutdown();
     ExtensionApiTest::TearDownInProcessBrowserTestFixture();
   }