This reverts commit 15905a2a.

Have not encountered fonts needing this, but same reasoning as
for morx (see previos commit.)

Broke in 8dcc1913

If sanitizer is left with another object, it wouldn't work.

Better fix coming soon.

Towards consolidating all array bsearch/...

Geeza Pro for example, relies on that for fancy mark positioning.

Fixes https://github.com/harfbuzz/harfbuzz/issues/1405

Affects morx/kerx run-time only currently.  Will adjust their sanitize next.

Fixes https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=11400

Fixes https://oss-fuzz.com/v2/testcase-detail/5754863779053568

Fixes https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=11367

Fixes https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=11312
Fixes https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=11305

Let the fuzzing bots rip this code apart...

Not needed now that we use GPOS attachment for cursive kerx.

Untested.

That's what the spec says for Backwards flag, only applicable to
formats 1 and 4.

Untested.

This, enables Format2 for kern table, which was disabled before.