Remove nonexported _ns_flagdata from public header.

Bug: http://b/28178111
Change-Id: I25dca710964099c4e07bf694635db75a72b38508
diff --git a/libc/dns/nameser/ns_parse.c b/libc/dns/nameser/ns_parse.c
index 2d6d530..3a1901a 100644
--- a/libc/dns/nameser/ns_parse.c
+++ b/libc/dns/nameser/ns_parse.c
@@ -52,6 +52,8 @@
 
 /* Public. */
 
+struct _ns_flagdata {  int mask, shift;  };
+
 /* These need to be in the same order as the nres.h:ns_flag enum. */
 const struct _ns_flagdata _ns_flagdata[16] = {
 	{ 0x8000, 15 },		/* qr. */
diff --git a/libc/include/arpa/nameser.h b/libc/include/arpa/nameser.h
index b31d840..a207eab 100644
--- a/libc/include/arpa/nameser.h
+++ b/libc/include/arpa/nameser.h
@@ -141,10 +141,6 @@
 };
 typedef struct ns_newmsg ns_newmsg;
 
-/* Private data structure - do not use from outside library. */
-struct _ns_flagdata {  int mask, shift;  };
-extern const struct _ns_flagdata _ns_flagdata[];
-
 /* Accessor macros - this is part of the public interface. */
 
 #define ns_msg_id(handle) ((handle)._id + 0)