SF: reduce timeout for unit tests

change the timeout used in transaction application
to make the unit tests run faster.

Bug: 198190384
Test: libsurfaceflinger_unittest
Change-Id: I92e19f1b2957b406c1b61d0b948c3fb0c1f61d6c
diff --git a/services/surfaceflinger/SurfaceFlinger.h b/services/surfaceflinger/SurfaceFlinger.h
index 8ca9982..9dee550 100644
--- a/services/surfaceflinger/SurfaceFlinger.h
+++ b/services/surfaceflinger/SurfaceFlinger.h
@@ -1375,6 +1375,8 @@
         nsecs_t compositeStart;
         nsecs_t presentEnd;
     } mPowerHintSessionData GUARDED_BY(SF_MAIN_THREAD);
+
+    nsecs_t mAnimationTransactionTimeout = s2ns(5);
 };
 
 } // namespace android