What steps will reproduce the problem?

Create an SkOrderedFontMgr manager and append two SkFontMgrs (or SkParagraph TypefaceFontProviders) to it. Calling the ordered mgr's onMatchFamily method will only succeed in matching against whichever mgr was appended first.

What is the expected output? What do you see instead?

The intent of the method is to step through all of the appended mgrs until a match is found. Instead, if the first mgr doesn't have a match, an empty match is returned and subsequent mgrs aren't queried.

Root cause

There is a bug in the test on line 58 where it is checking for a null return value from the child mgr's matchFamily method, but according to the docs this method never returns null. Instead it returns an empty SkFontStyleSet.

Possible solution

Changing the implementation to check for emptiness instead of nullness provides the proper behavior and the loop will continue iterating until a non-empty match is found:

sk_sp<SkFontStyleSet> SkOrderedFontMgr::onMatchFamily(const char familyName[]) const {
    for (const auto& fm : fList) {
        auto fs = fm->matchFamily(familyName)
        if (fs->count()>0){ 
            return fs; 
        }
    }
    return nullptr;
}