Fix GetAuthTokenFunctionPublicSessionTest.NonWhitelisted for Mash

Bug: 833144
Change-Id: I5fae6070f992e5cd0873b7172fc1ef009a881742
Reviewed-on: https://chromium-review.googlesource.com/c/1323893Reviewed-by: David Roger <droger@chromium.org>
Reviewed-by: Jun Mukai <mukai@chromium.org>
Commit-Queue: Evan Stade <estade@chromium.org>
Cr-Commit-Position: refs/heads/master@{#606142}

chrome/browser/extensions/api/identity/identity_apitest.cc

@@ -1998,6 +1998,9 @@ class GetAuthTokenFunctionPublicSessionTest : public GetAuthTokenFunctionTest {
         .WillRepeatedly(Return(false));
     EXPECT_CALL(*user_manager_, IsLoggedInAsPublicAccount())
         .WillRepeatedly(Return(true));
+    EXPECT_CALL(*user_manager_, GetLoggedInUsers())
+        .WillRepeatedly(testing::Invoke(user_manager_,
+                                        &chromeos::MockUserManager::GetUsers));
   }
 
   scoped_refptr<const Extension> CreateTestExtension(const std::string& id) {

testing/buildbot/filters/chromeos.single_process_mash.browser_tests.filter

@@ -47,6 +47,3 @@
 
 # Flaky https://crbug.com/887175
 -PrerenderBrowserTest.PrerenderHTML5VideoJs
-
-# Flaky tests. crbug.com/833144
--GetAuthTokenFunctionPublicSessionTest.NonWhitelisted