Make StringPiece to be std::string_view alias

Bug: 237583012
Test: build + boot + UTs

Change-Id: I849831f4466d3b9c7ec842b75256e7fcba77a0c0
diff --git a/cmds/idmap2/libidmap2/Idmap.cpp b/cmds/idmap2/libidmap2/Idmap.cpp
index 813dff1..7c0b937 100644
--- a/cmds/idmap2/libidmap2/Idmap.cpp
+++ b/cmds/idmap2/libidmap2/Idmap.cpp
@@ -317,7 +317,7 @@
   }
 
   std::unique_ptr<IdmapData> data(new IdmapData());
-  data->string_pool_data_ = resource_mapping.GetStringPoolData().to_string();
+  data->string_pool_data_ = std::string(resource_mapping.GetStringPoolData());
   uint32_t inline_value_count = 0;
   std::set<std::string> config_set;
   for (const auto& mapping : resource_mapping.GetTargetToOverlayMap()) {