Some clang versions define static_assert as a macro apparently, so we cannot
redefine it...

This reverts commit 94bfea0c.
This reverts commit 4e626278.

So we don't accidentally break it again.

Fix a bug in CBDT sanitize, and redundant check in avar.

Sorry for the noise, downstream custom builders.  Please adjust.

Such a headache that Windows defines UINT8, ...; Just prefix it.

With this, I believe MATH table API is not ready to be merged.

Note, the function now returns "half of horizontal advance width"
if top accent attachment for glyph is not explicitly defined.
This is what the spec requires.  Updated tests.

Not functional change (expected!).

This makes a lot of code safer.  We only try modifying the object in one
place, after making sure it's safe to do so.  So, do a const_cast<> in
that one place...

Simplifies hb_in_range() calls as the type can be inferred.
The rest is obsessiveness, I admit.