Bug 1343677 part 3. Remove all the CSS bits from the ContentPrefs whitelist. r=billm,dholbert

We're now asserting that we never check these before the END_ALL_PREFS phase,
which means they don't need to be sent to the content process synchronously.

MozReview-Commit-ID: 4BGbvVCjDWz

dom/ipc/ContentPrefs.cpp

@@ -105,48 +105,6 @@ const char* mozilla::dom::ContentPrefs::gInitPrefs[] = {
   "javascript.options.werror",
   "javascript.use_us_english_locale",
   "jsloader.reuseGlobal",
-  "layout.css.all-shorthand.enabled",
-  "layout.css.background-blend-mode.enabled",
-  "layout.css.background-clip-text.enabled",
-  "layout.css.box-decoration-break.enabled",
-  "layout.css.color-adjust.enabled",
-  "layout.css.contain.enabled",
-  "layout.css.control-characters.visible",
-  "layout.css.display-flow-root.enabled",
-  "layout.css.expensive-style-struct-assertions.enabled",
-  "layout.css.float-logical-values.enabled",
-  "layout.css.font-variations.enabled",
-  "layout.css.grid.enabled",
-  "layout.css.image-orientation.enabled",
-  "layout.css.initial-letter.enabled",
-  "layout.css.isolation.enabled",
-  "layout.css.mix-blend-mode.enabled",
-  "layout.css.osx-font-smoothing.enabled",
-  "layout.css.overflow-clip-box.enabled",
-  "layout.css.prefixes.animations",
-  "layout.css.prefixes.border-image",
-  "layout.css.prefixes.box-sizing",
-  "layout.css.prefixes.device-pixel-ratio-webkit",
-  "layout.css.prefixes.font-features",
-  "layout.css.prefixes.gradients",
-  "layout.css.prefixes.transforms",
-  "layout.css.prefixes.transitions",
-  "layout.css.prefixes.webkit",
-  "layout.css.scope-pseudo.enabled",
-  "layout.css.scroll-behavior.property-enabled",
-  "layout.css.scroll-snap.enabled",
-  "layout.css.servo.enabled",
-  "layout.css.shape-outside.enabled",
-  "layout.css.text-align-unsafe-value.enabled",
-  "layout.css.text-combine-upright-digits.enabled",
-  "layout.css.text-combine-upright.enabled",
-  "layout.css.text-justify.enabled",
-  "layout.css.touch_action.enabled",
-  "layout.css.unprefixing-service.enabled",
-  "layout.css.unprefixing-service.globally-whitelisted",
-  "layout.css.unprefixing-service.include-test-domains",
-  "layout.css.variables.enabled",
-  "layout.css.visited_links_enabled",
   "layout.idle_period.required_quiescent_frames",
   "layout.idle_period.time_limit",
   "layout.interruptible-reflow.enabled",