Make startup_tests build and work on Mac.

chrome/browser/automation/automation_provider_list_generic.cc

Index: chrome/browser/automation/automation_provider_list_generic.cc
diff --git a/chrome/browser/automation/automation_provider_list_generic.cc b/chrome/browser/automation/automation_provider_list_generic.cc
new file mode 100644
index 0000000000000000000000000000000000000000..868d509188b9dc6d65f849d68641879af95d6834
--- /dev/null
+++ b/chrome/browser/automation/automation_provider_list_generic.cc
@@ -0,0 +1,8 @@
+// Copyright (c) 2009 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/browser/automation/automation_provider_list.h"
+
+void AutomationProviderList::OnLastProviderRemoved() {
+}