Revert "Allow multiple styles for fallback fonts"

The change being reverted somehow alters the reference counting of
SkTypeface instances, resulting in prematurely freed font data, which
is the underlying issue with the disappearing clock on the lockscreen
(http://b/5004404).

This reverts commit 792a256ab723bbc4b55ba00194fe2a9195cae8c0.

Bug: 5004404
Change-Id: I5c3b225f860ce2dcfc0751bded2d842b43a2d3c4
1 file changed