Revert "Replace AssetManager with AssetManager2 implementation"

This reverts commit b20a0ce59f59cb5ec857748e056cc341dbd13b92.
diff --git a/libs/androidfw/AssetManager2.cpp b/libs/androidfw/AssetManager2.cpp
index 2fc8e95..415d3e3 100644
--- a/libs/androidfw/AssetManager2.cpp
+++ b/libs/androidfw/AssetManager2.cpp
@@ -265,6 +265,8 @@
 
 ApkAssetsCookie AssetManager2::FindEntry(uint32_t resid, uint16_t density_override,
                                          bool stop_at_first_match, FindEntryResult* out_entry) {
+  ATRACE_CALL();
+
   // Might use this if density_override != 0.
   ResTable_config density_override_config;
 
@@ -427,7 +429,9 @@
   for (size_t iteration = 0u; in_out_value->dataType == Res_value::TYPE_REFERENCE &&
                               in_out_value->data != 0u && iteration < kMaxIterations;
        iteration++) {
-    *out_last_reference = in_out_value->data;
+    if (out_last_reference != nullptr) {
+      *out_last_reference = in_out_value->data;
+    }
     uint32_t new_flags = 0u;
     cookie = GetResource(in_out_value->data, true /*may_be_bag*/, 0u /*density_override*/,
                          in_out_value, in_out_selected_config, &new_flags);