Only set acquire fences on overlay layers

Change-Id: I08e8173f83580de5a4e43a0ba5ea03e5ec6e8782
diff --git a/services/surfaceflinger/Layer.h b/services/surfaceflinger/Layer.h
index 29515f0..b6ae0ae 100644
--- a/services/surfaceflinger/Layer.h
+++ b/services/surfaceflinger/Layer.h
@@ -66,6 +66,7 @@
     // LayerBase interface
     virtual void setGeometry(HWComposer::HWCLayerInterface& layer);
     virtual void setPerFrameData(HWComposer::HWCLayerInterface& layer);
+    virtual void setAcquireFence(HWComposer::HWCLayerInterface& layer);
     virtual void onDraw(const DisplayHardware& hw, const Region& clip) const;
     virtual uint32_t doTransaction(uint32_t transactionFlags);
     virtual void lockPageFlip(bool& recomputeVisibleRegions);