+++ This bug was initially created as a clone of Bug #1128165 +++ From https://bugzilla.mozilla.org/show_bug.cgi?id=1128165#c11 Ensure that unsupported silk configurations such as the vsync compositor enabled but hardware-vsync disabled doesn't actually crash, but instead just disables silk.

Just a small check that we really only enable the vsync compositor or refresh driver if both the pref and hardware vsync are enabled.

Comment on attachment 8568040 [details] [diff] [review] Ensure vsync compositor and refresh driver are only enabled if hardware vsync is enabled Approval Request Comment [Feature/regressing bug #]: Project Silk, but 1071275 [User impact if declined]: If a user enables silk on nightly, then goes back to the dev edition, they can get into an infinite crash loop if they use the same profile. The bug only occurs due to a user enabling a pref in nightly in about:config then going back to the dev edition with the same profile. [Describe test coverage new/current, TreeHerder]: Manual testing, only occurs due to this patch not being uplifted before turning on Silk. [Risks and why]: Low, just an extra check to make sure we don't enable silk unless hardware vsync is enabled. [String/UUID change made/needed]: None