SF: Add onLayerDisplayed method to LayerBE

Add onLayerDisplayed method to LayerBE class and make the data
for the class private.

Merged-in: I2a5b03d542d46fc0c2e1d6d725fb87580980427d
Test: Compile/Run manually
Change-Id: I2a5b03d542d46fc0c2e1d6d725fb87580980427d
diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index c8a9f69..7ae5b21 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -2034,7 +2034,7 @@
                         displayDevice->getClientTargetAcquireFence());
             }
 
-            layer->onLayerDisplayed(releaseFence);
+            layer->getBE().onLayerDisplayed(releaseFence);
         }
 
         // We've got a list of layers needing fences, that are disjoint with
@@ -2043,7 +2043,7 @@
         if (!displayDevice->getLayersNeedingFences().isEmpty()) {
             sp<Fence> presentFence = getBE().mHwc->getPresentFence(hwcId);
             for (auto& layer : displayDevice->getLayersNeedingFences()) {
-                layer->onLayerDisplayed(presentFence);
+                layer->getBE().onLayerDisplayed(presentFence);
             }
         }