#define Null(Type) Null<typename hb_remove_const<typename hb_remove_reference<Type>::value>::value>()

raises:
  hb-blob.cc: In function 'hb_blob_t* hb_blob_get_empty()':
  hb-blob.cc:194: error: using 'typename' outside of template
  hb-blob.cc:194: error: using 'typename' outside of template

Removing "typename"s fixes the issue but makes newer compiler fail apparently.

Probably downstream can patch that locally till we get a solution.

run-shape-fuzzer-tests.py automatically runs valgrind if see available
but test/api runs it by request, we probably should normalize the approaches
later

Actually the check is right,

On -myanmar.hh, on that particular switch, OT_C is indic_category_t
but OT_D is myanmar_category_t so we are mixing the types in one variable.

And on -arabic.cc, step can goes one number higher than step_t enum in the
loop so we are actually using it as an unsinged int.

Behdad apparently not interested on them

* -Wshift-sign-overflow
* -Wmissing-prototypes

* Raise error on warnings on -everything
* Enable fontconfig to two bots
* Fix msan bot now that all of its real complain are gone

#1196

Fixes https://github.com/harfbuzz/harfbuzz/issues/1175

Default exit value is 77, which causes autotools to "skip" test.

https://github.com/harfbuzz/harfbuzz/issues/1174
https://github.com/harfbuzz/harfbuzz/issues/1175