Revert "Revert "DispSync: Always resync after inactivity""

This reverts commit 67264e930992e43ef3351b04692d4ca59cbb01ad.

We've fixed the kernel issues this exposed.

bug 28198793

Change-Id: Ie895cc0a815094cce4bee3b2bf45800ee1e2fdc3
diff --git a/services/surfaceflinger/EventThread.h b/services/surfaceflinger/EventThread.h
index 9ba179a..34654fa 100644
--- a/services/surfaceflinger/EventThread.h
+++ b/services/surfaceflinger/EventThread.h
@@ -77,7 +77,7 @@
 
 public:
 
-    EventThread(const sp<VSyncSource>& src);
+    EventThread(const sp<VSyncSource>& src, SurfaceFlinger& flinger);
 
     sp<Connection> createEventConnection() const;
     status_t registerDisplayEventConnection(const sp<Connection>& connection);
@@ -116,6 +116,7 @@
     // constants
     sp<VSyncSource> mVSyncSource;
     PowerHAL mPowerHAL;
+    SurfaceFlinger& mFlinger;
 
     mutable Mutex mLock;
     mutable Condition mCondition;