Re-enable the PostDelayed TaskQueue test on all platforms except Windows.

webrtc/base/task_queue_unittest.cc

Index: webrtc/base/task_queue_unittest.cc
diff --git a/webrtc/base/task_queue_unittest.cc b/webrtc/base/task_queue_unittest.cc
index d0b7550657836276ecb6e45ac2f181c8eb8df5f6..3af337dfaf338eda1a2c9e2db927217fdfebaae7 100644
--- a/webrtc/base/task_queue_unittest.cc
+++ b/webrtc/base/task_queue_unittest.cc
@@ -91,7 +91,13 @@ TEST(TaskQueueTest, PostFromQueue) {
   EXPECT_TRUE(event.Wait(1000));
 }
 
-TEST(TaskQueueTest, DISABLED_PostDelayed) {
+// Currently flaky on Windows. See issue 6610.
+#if defined(WEBRTC_WIN)
+#define MAYBE_PostDelayed DISABLED_PostDelayed
+#else
+#define MAYBE_PostDelayed PostDelayed
+#endif
+TEST(TaskQueueTest, MAYBE_PostDelayed) {
   static const char kQueueName[] = "PostDelayed";
   TaskQueue queue(kQueueName);