handle surfaces posts independently from composition

surfaceflinger will now handle each surface post
as soon as possible and handle the composition
itself at VSYNC time as usual.

Change-Id: I6b1ae33fd56062d86e5419ebab8def0ca5803fbf
diff --git a/services/surfaceflinger/MessageQueue.cpp b/services/surfaceflinger/MessageQueue.cpp
index 290fff4..1ff3567 100644
--- a/services/surfaceflinger/MessageQueue.cpp
+++ b/services/surfaceflinger/MessageQueue.cpp
@@ -133,8 +133,7 @@
 }
 
 void MessageQueue::invalidate() {
-//    mHandler->signalInvalidate();
-    mEvents->requestNextVsync();
+    mHandler->signalInvalidate();
 }
 
 void MessageQueue::refresh() {