[glib-networking] Improve comment on updating certificate hex in test file

[Michael Catanzaro <mcatanzaro src gnome org>]

commit 05dcede6ef3626a5674b03ae1f533fb7c72d44a1
Author: Michael Catanzaro <mcatanzaro gnome org>
Date:   Fri Aug 28 12:09:53 2015 -0500

    Improve comment on updating certificate hex in test file
    
    https://bugzilla.gnome.org/show_bug.cgi?id=754265

 tls/tests/file-database.c |    9 ++++++++-
 1 files changed, 8 insertions(+), 1 deletions(-)
---
diff --git a/tls/tests/file-database.c b/tls/tests/file-database.c
index a487edf..40e292a 100644
--- a/tls/tests/file-database.c
+++ b/tls/tests/file-database.c
@@ -466,7 +466,14 @@ certificate_is_in_list (GList *certificates,
 static void
 test_lookup_certificates_issued_by (void)
 {
-  /* This data is generated from the frob-certificate test tool in gcr library */
+  /* This data is generated from the frob-certificate test tool in gcr library.
+   * To regenerate (from e.g. a directory containing gcr and glib-networking):
+   *
+   * $ gcr/frob-certificate glib-networking/tls/tests/files/ca.pem
+   *
+   * Then copy the hex that is printed after "subject" (not "issuer"!) and add
+   * the missing 'x's.
+   */
   const guchar ISSUER[] = "\x30\x81\x86\x31\x13\x30\x11\x06\x0A\x09\x92\x26\x89\x93\xF2"
                           "\x2C\x64\x01\x19\x16\x03\x43\x4F\x4D\x31\x17\x30\x15\x06\x0A"
                           "\x09\x92\x26\x89\x93\xF2\x2C\x64\x01\x19\x16\x07\x45\x58\x41"