Remove no longer existing friend.

sk_fontmgr_create_default used to exist before SkFontMgr::RefDefault
could do the job better. There are no actual implementations for this
function, so SkFontMgr should no longer be friends with it.

TBR=reed
Removes a deceased friend.

Review-Url: https://codereview.chromium.org/2232963002
1 file changed