[mutter] cogl: Make cogl-config.h include check explicit

[Georges Basile Stavracas Neto <gbsneto src gnome org>]

commit d68fcbc8879b85a50e54b282814747617d8fbe50
Author: Jonas Ådahl <jadahl gmail com>
Date:   Mon May 21 22:18:03 2018 +0200

    cogl: Make cogl-config.h include check explicit
    
    Don't rely on some combination of macros, but an explicit definition to
    check whether cogl-config.h was included.

 cogl/cogl-mutter-config.h.in | 2 ++
 cogl/cogl/cogl-util.h        | 4 +---
 cogl/configure.ac            | 2 ++
 3 files changed, 5 insertions(+), 3 deletions(-)
---
diff --git a/cogl/cogl-mutter-config.h.in b/cogl/cogl-mutter-config.h.in
index 25652ce55..2c8967811 100644
--- a/cogl/cogl-mutter-config.h.in
+++ b/cogl/cogl-mutter-config.h.in
@@ -3,3 +3,5 @@
 
 /* Have GLES 2.0 for rendering */
 #undef HAVE_COGL_GLES2
+
+#define COGL_CONFIG_H_INCLUDED 1
diff --git a/cogl/cogl/cogl-util.h b/cogl/cogl/cogl-util.h
index 70259d387..b8132220a 100644
--- a/cogl/cogl/cogl-util.h
+++ b/cogl/cogl/cogl-util.h
@@ -40,9 +40,7 @@
 #include <stdio.h>
 
 /* Double check that config.h has been included */
-#if (!defined (PACKAGE_NAME) && \
-     !defined (_COGL_IN_TEST_BITMASK) && \
-     !defined(COGL_ENABLE_MUTTER_API))
+#ifndef COGL_CONFIG_H_INCLUDED
 #error "cogl-config.h must be included before including cogl-util.h"
 #endif
 
diff --git a/cogl/configure.ac b/cogl/configure.ac
index 92ea712ac..4c3f2eb2c 100644
--- a/cogl/configure.ac
+++ b/cogl/configure.ac
@@ -673,6 +673,8 @@ AC_SUBST(COGL_EXTRA_LDFLAGS)
 MAINTAINER_CFLAGS=
 AC_SUBST(MAINTAINER_CFLAGS)
 
+AC_DEFINE([COGL_CONFIG_H_INCLUDED], 1, [cogl-config.h was included])
+
 AC_OUTPUT(
 Makefile
 test-fixtures/Makefile