[pygobject] configure.ac: only enable code coverage when available

[Martin Pitt <martinpitt src gnome org>]

commit f6d4d2da676ae63d7a24dd172775b488ce665fe4
Author: Jonathan Ballet <jon multani info>
Date:   Thu Feb 14 07:50:02 2013 +0100

    configure.ac: only enable code coverage when available
    
    When building with an older gnome-common which does not yet provide code
    coverage support, disable it instead of breaking the configure script.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=693328

 configure.ac |   10 +++++++++-
 1 files changed, 9 insertions(+), 1 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 9b7a72e..c73d093 100644
--- a/configure.ac
+++ b/configure.ac
@@ -228,7 +228,15 @@ AC_SUBST(INTROSPECTION_COMPILER)
 
 # compiler warnings, errors, required cflags, and code coverage support
 GNOME_COMPILE_WARNINGS([maximum])
-GNOME_CODE_COVERAGE
+AC_MSG_CHECKING(for Gnome code coverage support)
+m4_ifdef([GNOME_CODE_COVERAGE],
+         [AC_MSG_RESULT(yes)
+          GNOME_CODE_COVERAGE],
+         [AC_MSG_RESULT(no)
+          GNOME_CODE_COVERAGE_RULES=''
+          AC_SUBST([GNOME_CODE_COVERAGE_RULES])
+          enable_code_coverage="no"])
+
 if test "x$GCC" = "xyes"; then
   JH_ADD_CFLAG([-Wall])
   JH_ADD_CFLAG([-Werror=unused-variable])