Bug 1207000 - Create GMPVideoDecoderTrialCreator on all platforms. r=edwin

dom/media/eme/MediaKeySystemAccessManager.cpp

@@ -51,9 +51,7 @@ NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
 MediaKeySystemAccessManager::MediaKeySystemAccessManager(nsPIDOMWindow* aWindow)
   : mWindow(aWindow)
   , mAddedObservers(false)
-#ifdef XP_WIN
   , mTrialCreator(new GMPVideoDecoderTrialCreator())
-#endif
 {
 }