Revert "Layer: Use raw pointers for Current/Drawing parent"

This reverts commit cbdb79a195e6c690e16948a7e7c3abbd36414b17.

Bug: 203175614
Bug: 203559094
Change-Id: I5432ad46bfbbe5a009e3fb72ae7ac129263260ce
diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index acb81dc..81f20ed 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -3412,7 +3412,6 @@
     states.add(composerState);
 
     lbc->updateTransformHint(mActiveDisplayTransformHint);
-
     if (outTransformHint) {
         *outTransformHint = mActiveDisplayTransformHint;
     }
@@ -3957,7 +3956,7 @@
     }
     if (what & layer_state_t::eLayerChanged) {
         // NOTE: index needs to be calculated before we update the state
-        auto p = layer->getParent();
+        const auto& p = layer->getParent();
         if (p == nullptr) {
             ssize_t idx = mCurrentState.layersSortedByZ.indexOf(layer);
             if (layer->setLayer(s.z) && idx >= 0) {
@@ -3975,7 +3974,7 @@
     }
     if (what & layer_state_t::eRelativeLayerChanged) {
         // NOTE: index needs to be calculated before we update the state
-        auto p = layer->getParent();
+        const auto& p = layer->getParent();
         const auto& relativeHandle = s.relativeLayerSurfaceControl ?
                 s.relativeLayerSurfaceControl->getHandle() : nullptr;
         if (p == nullptr) {
@@ -6126,7 +6125,7 @@
                 return;
             }
 
-            auto p = layer;
+            sp<Layer> p = layer;
             while (p != nullptr) {
                 if (excludeLayers.count(p) != 0) {
                     return;