Backed out changeset 718a9852b60d (bug 899785) for near-permanent reftest failures on Windows CLOSED TREE

modules/libpref/src/init/all.js

@@ -3734,14 +3734,10 @@ pref("layers.offmainthreadcomposition.frame-rate", -1);
 #ifndef XP_WIN
 // Asynchonous video compositing using the ImageBridge IPDL protocol.
 // requires off-main-thread compositing.
+// Never works on Windows, so no point pref'ing it on.
 pref("layers.async-video.enabled",false);
 #endif
 
-#ifdef XP_WIN
-pref("layers.offmainthreadcomposition.enabled", true);
-pref("layers.async-video.enabled", true);
-#endif
-
 #ifdef MOZ_X11
 // OMTC off by default on Linux, but if activated, use new textures and async-video.
 pref("layers.async-video.enabled", true);