* Toggle animate=false attribute on arrow panels when toolkit.cosmeticAnimations.enabled is false * Use preferences-service component to lookup the pref in the arrowpanel binding * Disable this pref during tests to remove a source of instability and timing-based test failures in chrome/UI tests. * Enable cosmeticAnimations for tests which depend on existing behavior MozReview-Commit-ID: IvA2ySPPmeJ