Revert of Simple cleanups related to SkFixed. (patchset #4 id:120001 of https://codereview.chromium.org/1683743005/ )

Reason for revert:
New test is failing on Windows.

Original issue's description:
> Cleanups related to SkFixed.
>
> Remove SK_FixedNaN. It does not seem to be supported or used anywhere in Skia, Chromium, Android, or Google3, (except accidentally by TwoPtRadial::kDontDrawT). I think supporting it would erase any benefit of SkFixed over float.
>
> Remove SkBitmapFilter::lookup. It does not appear to be used anywhere in Skia, Chromium, Android, or Google3.
>
> Fix a bug in SkPaint::breakText that limited it to ~5kB of text. Now it can handle more than 1GB.
>
> BUG=skia:4632
> GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1683743005
>
> Committed: https://skia.googlesource.com/skia/+/7ea5cb18389db11a94175de95c9db2b44972630c

TBR=mtklein@google.com,reed@google.com
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=skia:4632

Review URL: https://codereview.chromium.org/1724283003
7 files changed