Bug 1711724 - Ship CanvasRenderingContext2D.createConicGradient. r=annevk

Passes all the WPTs afaict.

Differential Revision: https://phabricator.services.mozilla.com/D115471

modules/libpref/init/StaticPrefList.yaml

@@ -1365,7 +1365,7 @@
 # Is support for CanvasRenderingContext2D's createConicGradient API enabled?
 - name: canvas.createConicGradient.enabled
   type: RelaxedAtomicBool
-  value: @IS_NIGHTLY_BUILD@
+  value: true
   mirror: always
 
 # Provide ability to turn on support for canvas mozGetAsFile API.