Backed out changeset 017aa3b39d73 (bug 1675853) for causing wpt failures in ch-pseudo-recalc-on-font-load.html

CLOSED TREE

layout/style/FontFace.cpp

@@ -328,6 +328,8 @@ FontFaceLoadStatus FontFace::Status() { return mStatus; }
 Promise* FontFace::Load(ErrorResult& aRv) {
   MOZ_ASSERT(NS_IsMainThread());
 
+  mFontFaceSet->FlushUserFontSet();
+
   EnsurePromise();
 
   if (!mLoaded) {