Disable TwoClientPasswordsSyncTest.SetPassphraseAndThenSetupSync on Mac.

chrome/browser/sync/test/integration/two_client_passwords_sync_test.cc

Index: chrome/browser/sync/test/integration/two_client_passwords_sync_test.cc
diff --git a/chrome/browser/sync/test/integration/two_client_passwords_sync_test.cc b/chrome/browser/sync/test/integration/two_client_passwords_sync_test.cc
index c9a89e19e3cb2365558fefa13d895300f26ea92f..aaacb96a96bb80c9c564a66f8f07e3360246e4dc 100644
--- a/chrome/browser/sync/test/integration/two_client_passwords_sync_test.cc
+++ b/chrome/browser/sync/test/integration/two_client_passwords_sync_test.cc
@@ -143,8 +143,14 @@ IN_PROC_BROWSER_TEST_F(TwoClientPasswordsSyncTest, Delete) {
   ASSERT_TRUE(AllProfilesContainSamePasswordFormsAsVerifier());
 }
 
+// Flaky on Mac: https://crbug.com/639449
+#if defined(OS_MACOSX)
+#define MAYBE_SetPassphraseAndThenSetupSync DISABLED_SetPassphraseAndThenSetupSync
+#else
+#define MAYBE_SetPassphraseAndThenSetupSync SetPassphraseAndThenSetupSync
+#endif
 IN_PROC_BROWSER_TEST_F(TwoClientPasswordsSyncTest,
-                       SetPassphraseAndThenSetupSync) {
+                       MAYBE_SetPassphraseAndThenSetupSync) {
   ASSERT_TRUE(SetupClients());
 
   ASSERT_TRUE(GetClient(0)->SetupSync());