* add fd index checks to subr subsetter

also added oss-fuzz test case

* undid SubrSubsetParam::is_valid

because already validated by SubrClosures.valid

Will become default and option removed in the future.

This reverts commit 7146718b.

Fixing differently.

Few fixes for Visual Studio builds

We were dereferencing Null pointers and trying to sanitize them,
which is not necessary...

Ha!

* fix oss-fuzz 11690: substr.offset >= opStart

detect recursive subroutine call & handle as error

* fix build failure

* add minimized test case for oss-fuzz 11690

* removed asserts

Fixes https://github.com/harfbuzz/harfbuzz/issues/1470

Ensure variables are declared at the top of the block.

We need to add -DHB_AAT_H and -DHB_AAT_H_IN to the flags that are passed
to g-ir-scanner, so that introspection builds can proceed normally.

Things to be used in https://github.com/harfbuzz/harfbuzz/pull/1459

Added case for OpCode_BaseFontName. This opcode in spec but practically unused.
Added a comment for default case which can't be hit

* pass subarray of stack to set_blends

* get_subarray to return a value, not ref

* restored error check (with tweak)

Ouch!

[CFF] oss-fuzz issue 11714: set_blends

[CFF] oss-fuzz issue 11713 (CFF2VariationStore::serialize)

[CFF] fix oss-fuzz issue 11691 (BlendArg::set_blends)