[devhelp] build: disable -Werror by default

[Sébastien Wilmet <swilmet src gnome org>]

commit d03e84c5ece70a1c863527e6510a0aca7faf3d8d
Author: Sébastien Wilmet <swilmet gnome org>
Date:   Mon Apr 3 07:55:15 2017 +0200

    build: disable -Werror by default
    
    See this thread:
    https://mail.gnome.org/archives/desktop-devel-list/2017-April/msg00000.html
    
    -Werror was anyway already disabled by default in Jhbuild.

 configure.ac |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index dbe5d88..e76e92d 100644
--- a/configure.ac
+++ b/configure.ac
@@ -49,8 +49,10 @@ GLIB_GSETTINGS
 AX_REQUIRE_DEFINED([GOBJECT_INTROSPECTION_CHECK])
 GOBJECT_INTROSPECTION_CHECK([1.30.0])
 
+# Compile warnings. There can be deprecation warnings at any time, so disable
+# -Werror by default with the [yes] argument.
 AX_REQUIRE_DEFINED([AX_COMPILER_FLAGS])
-AX_COMPILER_FLAGS
+AX_COMPILER_FLAGS([WARN_CFLAGS], [WARN_LDFLAGS], [yes])
 
 LT_LIB_M