[gnome-desktop] Bump soname

[Michael Catanzaro <mcatanzaro src gnome org>]

commit 02f772f9bcf11f1120a48e8428a48ace989af439
Author: Michael Catanzaro <mcatanzaro igalia com>
Date:   Wed Jul 17 13:45:47 2019 -0500

    Bump soname
    
    For the ABI break in !47.

 meson.build | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)
---
diff --git a/meson.build b/meson.build
index 39b0e438..4370878a 100644
--- a/meson.build
+++ b/meson.build
@@ -10,8 +10,11 @@ project('gnome-desktop', 'c',
 #  * Bump the second component if new APIs are added; or
 #  * Bump the third component otherwise.
 #
+# When bumping the first component version, set the second and third components
+# to 0. When bumping the second version, set the third one to zero.
+#
 # A lot easier than libtool, right?
-libversion = '17.1.7'
+libversion = '18.0.0'
 soversion = libversion.split('.')[0]
 
 gdk_pixbuf_req = '>= 2.36.5'