Disable ExtensionsStartupTest.NoFileAccess on Mac.

chrome/browser/extensions/extension_startup_browsertest.cc

 // Copyright (c) 2008 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 <vector>
 
 #include "base/command_line.h"
 #include "base/file_path.h"
 #include "base/file_util.h"
 #include "base/path_service.h"
@@ skipping 126 matching lines @@
   ExtensionsStartupTest() {
     enable_extensions_ = true;
   }
 };
 
 IN_PROC_BROWSER_TEST_F(ExtensionsStartupTest, Test) {
   WaitForServicesToStart(4, true);  // 1 component extension and 3 others.
   TestInjection(true, true);
 }
 
+// Sometimes times out on Mac.  http://crbug.com/48151
+#if defined(OS_MACOSX)
+#define MAYBE_NoFileAccess DISABLED_NoFileAccess
+#else
+#define MAYBE_NoFileAccess NoFileAccess
+#endif
 // Tests that disallowing file access on an extension prevents it from injecting
 // script into a page with a file URL.
-IN_PROC_BROWSER_TEST_F(ExtensionsStartupTest, NoFileAccess) {
+IN_PROC_BROWSER_TEST_F(ExtensionsStartupTest, MAYBE_NoFileAccess) {
   WaitForServicesToStart(4, true);  // 1 component extension and 3 others.
 
   ExtensionsService* service = browser()->profile()->GetExtensionsService();
   for (size_t i = 0; i < service->extensions()->size(); ++i) {
     if (service->AllowFileAccess(service->extensions()->at(i))) {
       service->SetAllowFileAccess(service->extensions()->at(i), false);
       ui_test_utils::WaitForNotification(
            NotificationType::USER_SCRIPTS_UPDATED);
     }
   }
@@ skipping 21 matching lines @@
 // Flaky (times out) on Mac/Windows. http://crbug.com/46301.
 #if defined(OS_MACOSX) || defined(OS_WIN)
 #define MAYBE_Test FLAKY_Test
 #else
 #define MAYBE_Test Test
 #endif
 IN_PROC_BROWSER_TEST_F(ExtensionsLoadTest, MAYBE_Test) {
   WaitForServicesToStart(1, false);
   TestInjection(true, true);
 }