typing: Fix the cache insertion guard to check for meta-types.
typing: Fix the cache insertion guard to check for meta-types.

twoporeguys/librpc,twoporeguys/librpc,twoporeguys/librpc,twoporeguys/librpc,twoporeguys/librpc,twoporeguys/librpc,twoporeguys/librpc,twoporeguys/librpc