Fix flaky SessionCleanupCookieStoreTest.TestDeleteSessionCookies

This should ensure the delete tasks get run.

Bug: 854032
Cq-Include-Trybots: luci.chromium.try:linux_mojo
Change-Id: I73304bee8ee59e3e30ecb060cd3288c2630c8191
Reviewed-on: https://chromium-review.googlesource.com/1106479Reviewed-by: John Abd-El-Malek <jam@chromium.org>
Commit-Queue: Clark DuVall <cduvall@chromium.org>
Cr-Commit-Position: refs/heads/master@{#568701}

services/network/session_cleanup_cookie_store_unittest.cc

@@ -13,7 +13,6 @@
 #include "base/task_scheduler/task_scheduler.h"
 #include "base/test/scoped_task_environment.h"
 #include "base/time/time.h"
-#include "build/build_config.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "url/gurl.h"
 
@@ -127,11 +126,6 @@ TEST_F(SessionCleanupCookieStoreTest, TestPersistence) {
   cookies.clear();
 }
 
-#if defined(OS_LINUX) || defined(OS_CHROMEOS) || defined(OS_ANDROID)
-#define MAYBE_TestDeleteSessionCookies DISABLED_TestDeleteSessionCookies
-#else
-#define MAYBE_TestDeleteSessionCookies TestDeleteSessionCookies
-#endif
 TEST_F(SessionCleanupCookieStoreTest, TestDeleteSessionCookies) {
   CanonicalCookieVector cookies = CreateAndLoad();
   ASSERT_EQ(0u, cookies.size());
@@ -161,6 +155,7 @@ TEST_F(SessionCleanupCookieStoreTest, TestDeleteSessionCookies) {
       base::BindRepeating([](const std::string& domain, bool is_https) {
         return domain == "nonpersistent.com";
       }));
+  scoped_task_environment_.RunUntilIdle();
   DestroyStore();
   cookies = CreateAndLoad();
 
@@ -198,6 +193,7 @@ TEST_F(SessionCleanupCookieStoreTest, ForceKeepSessionState) {
       base::BindRepeating([](const std::string& domain, bool is_https) {
         return domain == "nonpersistent.com";
       }));
+  scoped_task_environment_.RunUntilIdle();
   DestroyStore();
   cookies = CreateAndLoad();