Track pendingBuffer count in RequestedLayerState

Allows for easier retrieval without added lock contention.
RequestedLayerState stores a pointer to the original
buffer count from legacy layer.

Bug: b/294922229
Test: presubmit
Flag: EXEMPT, mechanical refactor
Change-Id: Iaab1b2214cc670f6e2d385ba4aba31e635a34030
diff --git a/services/surfaceflinger/FrontEnd/LayerCreationArgs.h b/services/surfaceflinger/FrontEnd/LayerCreationArgs.h
index 0788d1a..07a5724 100644
--- a/services/surfaceflinger/FrontEnd/LayerCreationArgs.h
+++ b/services/surfaceflinger/FrontEnd/LayerCreationArgs.h
@@ -61,6 +61,7 @@
     ui::LayerStack layerStackToMirror = ui::INVALID_LAYER_STACK;
     uint32_t parentId = UNASSIGNED_LAYER_ID;
     uint32_t layerIdToMirror = UNASSIGNED_LAYER_ID;
+    std::atomic<int32_t>* pendingBuffers = 0;
 };
 
 } // namespace android::surfaceflinger