Bug 1579624 - Turn on "layout.css.line-height.normal-as-resolved-value.enabled" in all channels. r=dholbert

Differential Revision: https://phabricator.services.mozilla.com/D45129

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

modules/libpref/init/StaticPrefList.yaml

@@ -5261,7 +5261,7 @@
 # [1]: https://github.com/w3c/csswg-drafts/issues/3749#issuecomment-477287453
 - name: layout.css.line-height.normal-as-resolved-value.enabled
   type: bool
-  value: @IS_EARLY_BETA_OR_EARLIER@
+  value: true
   mirror: always
 
 # Are the width and height attributes on image-like elements mapped to the