Bug 1594708 - Enable formdata event by default; r=edgar

Differential Revision: https://phabricator.services.mozilla.com/D52172

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

dom/tests/mochitest/general/test_interfaces.js

@@ -384,7 +384,7 @@ var interfaceNamesInGlobalScope = [
   // IMPORTANT: Do not change this list without review from a DOM peer!
   { name: "FormData", insecureContext: true },
   // IMPORTANT: Do not change this list without review from a DOM peer!
-  { name: "FormDataEvent", insecureContext: true, nightly: true },
+  { name: "FormDataEvent", insecureContext: true },
   // IMPORTANT: Do not change this list without review from a DOM peer!
   { name: "FontFace", insecureContext: true },
   // IMPORTANT: Do not change this list without review from a DOM peer!

modules/libpref/init/StaticPrefList.yaml

@@ -1501,10 +1501,10 @@
   value: false
   mirror: always
 
-# Whether or not formData event is enabled.
+# Enable formData event
 - name: dom.formdata.event.enabled
   type: bool
-  value: @IS_NIGHTLY_BUILD@
+  value: true
   mirror: always
 
 # Support @autocomplete values for form autofill feature.