Expose the upb_ByteSize function to upb clients. Note that the current naive implementation is no more efficient than serializing the message yourself and noting the resulting size.

PiperOrigin-RevId: 729190911

Author: eamonnmcmanus

upb/BUILD

@@ -203,6 +203,12 @@ alias(
     visibility = ["//visibility:public"],
 )
 
+alias(
+    name = "wire_byte_size",
+    actual = "//upb/wire:byte_size",
+    visibility = ["//upb:friends"],
+)
+
 alias(
     name = "wire_reader",
     actual = "//upb/wire:reader",