[pitivi/1.0] flatpak: Build libunwind to be able to retrieve useful stacktraces

[Thibault Saunier <tsaunier src gnome org>]

commit 7d2331dd5c7714584c690fa711951511a5f27ded
Author: Thibault Saunier <tsaunier igalia com>
Date:   Wed Jul 18 15:51:01 2018 -0400

    flatpak: Build libunwind to be able to retrieve useful stacktraces
    
    Using Gst.debug_print_stack_trace()

 build/flatpak/org.pitivi.Pitivi.json | 10 ++++++++++
 1 file changed, 10 insertions(+)
---
diff --git a/build/flatpak/org.pitivi.Pitivi.json b/build/flatpak/org.pitivi.Pitivi.json
index 7a44c156..268668fe 100644
--- a/build/flatpak/org.pitivi.Pitivi.json
+++ b/build/flatpak/org.pitivi.Pitivi.json
@@ -383,6 +383,16 @@
                 }
             ]
         },
+        {
+            "name": "libunwind",
+            "sources": [
+                {
+                    "type": "git",
+                    "url": "https://github.com/libunwind/libunwind.git";,
+                    "commit": "v1.2.1"
+                }
+            ]
+        },
         {
             "name": "gstreamer",
             "buildsystem": "meson",