Set `NON_ZERO_SIZED` flag correctly for struct/union ctors
Set `NON_ZERO_SIZED` flag correctly for struct/union ctors

And for methods/functions as well, they are zero-sized now

aidancully/rust,GBGamer/rust,GBGamer/rust,aidancully/rust,aidancully/rust,graydon/rust,graydon/rust,GBGamer/rust,aidancully/rust,graydon/rust,aidancully/rust,GBGamer/rust,GBGamer/rust,aidancully/rust,GBGamer/rust,GBGamer/rust,GBGamer/rust,graydon/rust,graydon/rust,graydon/rust