Refactor the attached method invokers to use a pool of MethodHandles with pre-set closures.  Avoids chewing up a page per invoker when running on older libffi.
Refactor the attached method invokers to use a pool of MethodHandles with pre-set closures.  Avoids chewing up a page per invoker when running on older libffi.

ffi/ffi,MikaelSmith/ffi,tduehr/ffi,yghannam/ffi,majioa/ffi,ferventcoder/ffi,ffi/ffi,yghannam/ffi,tduehr/ffi,ferventcoder/ffi,yghannam/ffi,ferventcoder/ffi,mvz/ffi,mvz/ffi,majioa/ffi,sparkchaser/ffi,tduehr/ffi,ffi/ffi,sparkchaser/ffi,majioa/ffi,tduehr/ffi,yghannam/ffi,mvz/ffi,MikaelSmith/ffi,ferventcoder/ffi,sparkchaser/ffi,yghannam/ffi,mvz/ffi,majioa/ffi,sparkchaser/ffi,MikaelSmith/ffi,MikaelSmith/ffi