[SF] Updates to not send hints without a present being followed

Updates the hint to be sent through a frame scheduling.
Reduce the number of callbacks to notifyExpectedPresentIfRequired
by making calls only through EventThread.
Timeout hint is sent directly without scheduling a frame
to avoid delay in sending the hint.
A hint through setTransactionState for ScheduleOnTx will
be in a follow up CL

BUG: 316615878
Test: atest NotifyExpectedPresentTest
Change-Id: I60f555d69626656901951808353f4a632e9b5e71
diff --git a/services/surfaceflinger/Scheduler/EventThread.h b/services/surfaceflinger/Scheduler/EventThread.h
index 8970103..90e61a9 100644
--- a/services/surfaceflinger/Scheduler/EventThread.h
+++ b/services/surfaceflinger/Scheduler/EventThread.h
@@ -142,6 +142,7 @@
     virtual bool throttleVsync(TimePoint, uid_t) = 0;
     virtual Period getVsyncPeriod(uid_t) = 0;
     virtual void resync() = 0;
+    virtual void onExpectedPresentTimePosted(TimePoint) = 0;
 };
 
 namespace impl {