[gnome-builder] flatpak: bring back tracing for nightly

[Christian Hergert <chergert src gnome org>]

commit 3c3be302a6540d81f887cdd569eae089dc2bd1cc
Author: Christian Hergert <chergert redhat com>
Date:   Fri Feb 22 22:47:42 2019 -0800

    flatpak: bring back tracing for nightly

 build-aux/flatpak/org.gnome.Builder.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/build-aux/flatpak/org.gnome.Builder.json b/build-aux/flatpak/org.gnome.Builder.json
index c80a4edcc..0fde99842 100644
--- a/build-aux/flatpak/org.gnome.Builder.json
+++ b/build-aux/flatpak/org.gnome.Builder.json
@@ -554,7 +554,7 @@
                 "-Dfusermount_wrapper=true",
                 "-Dwith_tcmalloc=true",
                 "-Dpython_libprefix=python3.7",
-                "-Denable_tracing=false",
+                "-Denable_tracing=true",
                 "-Dwith_help=true",
                 "-Dwith_channel=flatpak-nightly",
                 "-Dwith_deviced=true"