Disable all the browser_tests that are flaking more than 5% of the time on trybots.

chrome/browser/profiles/profile_manager_browsertest.cc

 // Copyright (c) 2012 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 "base/bind.h"
 #include "base/command_line.h"
 #include "base/prefs/pref_service.h"
 #include "base/strings/utf_string_conversions.h"
 #include "chrome/browser/password_manager/password_store_factory.h"
 #include "chrome/browser/profiles/profile_info_cache.h"
@@ skipping 312 matching lines @@
   profiles::SwitchToProfile(path_profile1, desktop_type, false,
                             kOnProfileSwitchDoNothing,
                             ProfileMetrics::SWITCH_PROFILE_ICON);
   EXPECT_EQ(chrome::GetTotalBrowserCount(), 2U);
   EXPECT_EQ(2U, browser_list->size());
 
   EXPECT_EQ(path_profile1, browser_list->get(0)->profile()->GetPath());
   EXPECT_EQ(path_profile2, browser_list->get(1)->profile()->GetPath());
 }
 
-// This test used to be flakily timing out on Windows: http://crbug.com/314905.
-// If this happens again please make it a MAYBE_ test and reopen that bug.
-IN_PROC_BROWSER_TEST_F(ProfileManagerBrowserTest, EphemeralProfile) {
+// Flakes on Windows: http://crbug.com/314905
+#if defined(OS_WIN)
+#define MAYBE_EphemeralProfile DISABLED_EphemeralProfile
+#else
+#define MAYBE_EphemeralProfile EphemeralProfile
+#endif
+IN_PROC_BROWSER_TEST_F(ProfileManagerBrowserTest, MAYBE_EphemeralProfile) {
 #if defined(OS_WIN) && defined(USE_ASH)
   // Disable this test in Metro+Ash for now (http://crbug.com/262796).
   if (CommandLine::ForCurrentProcess()->HasSwitch(switches::kAshBrowserTests))
     return;
 #endif
 
   // If multiprofile mode is not enabled, you can't switch between profiles.
   if (!profiles::IsMultipleProfilesEnabled())
     return;
 
@@ skipping 93 matching lines @@
       run_loop.QuitClosure());
   EXPECT_TRUE(password_store->ScheduleTask(task));
   run_loop.Run();
 
   EXPECT_TRUE(verify_add.IsCalled());
   EXPECT_EQ(1u, verify_add.GetPasswords().size());
   EXPECT_TRUE(verify_delete.IsCalled());
   EXPECT_EQ(0u, verify_delete.GetPasswords().size());
 }
 #endif  // !defined(OS_WIN) && !defined(OS_ANDROID) && !defined(OS_CHROMEOS)