Bug 1582530 - Turn on 'layout.css.xul-box-display-values.survive-blockification.enabled' by default. r=dholbert

Differential Revision: https://phabricator.services.mozilla.com/D46675

--HG--
extra : moz-landing-system : lando

modules/libpref/init/StaticPrefList.yaml

@@ -5013,7 +5013,7 @@
 # "blockified" to "-moz-box" (rather than to "block")
 - name: layout.css.xul-box-display-values.survive-blockification.enabled
   type: RelaxedAtomicBool
-  value: false
+  value: true
   mirror: always
   rust: true