Prevent double uri_escaping in chan_sip when pedantic is enabled

If pedantic mode is enabled, outbound invites will have double-escaped
contacts.  This avoids setting an already-escaped string into a field
where it is expected to be unescaped.

(closes issue ASTERISK-20023)
Reported by: Walter Doekes
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Merged revisions 369993 from http://svn.asterisk.org/svn/asterisk/branches/1.8
........

Merged revisions 369994 from http://svn.asterisk.org/svn/asterisk/branches/10


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@369995 65c4cc65-6c06-0410-ace0-fbb531ad65f3

channels/chan_sip.c

@@ -12855,11 +12855,11 @@ static void initreqprep(struct sip_request *req, struct sip_pvt *p, int sipmetho
 	else /* Save for any further attempts */
 		ast_string_field_set(p, fromname, n);
+	ast_copy_string(tmp_l, l, sizeof(tmp_l));
 	if (sip_cfg.pedanticsipchecking) {
 		ast_escape_quoted(n, tmp_n, sizeof(tmp_n));
 		n = tmp_n;
 		ast_uri_encode(l, tmp_l, sizeof(tmp_l), ast_uri_sip_user);
-		l = tmp_l;
 	}
 	ourport = (p->fromdomainport) ? p->fromdomainport : ast_sockaddr_port(&p->ourip);
@@ -12873,10 +12873,10 @@ static void initreqprep(struct sip_request *req, struct sip_pvt *p, int sipmetho
 	if (!sip_standard_port(p->socket.type, ourport)) {
 		size_t offset = strlen(from);
-		snprintf(&from[offset], sizeof(from) - offset, "<sip:%s@%s:%d>;tag=%s", l, d, ourport, p->tag);
+		snprintf(&from[offset], sizeof(from) - offset, "<sip:%s@%s:%d>;tag=%s", tmp_l, d, ourport, p->tag);
 	} else {
 		size_t offset = strlen(from);
-		snprintf(&from[offset], sizeof(from) - offset, "<sip:%s@%s>;tag=%s", l, d, p->tag);
+		snprintf(&from[offset], sizeof(from) - offset, "<sip:%s@%s>;tag=%s", tmp_l, d, p->tag);
 	}
 	if (!ast_strlen_zero(explicit_uri)) {