PR14763: Debug info for non-trivial record parameters

There seems to have been some erroneous code attempting to describe the
ABI of parameters (non-trivial record parameters are passed by
reference). This would break the type of the function (especially when
it caused a mismatch between the type of a declaration & a definition)
causing PR14763 and PR14645.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@183329 91177308-0d34-0410-b5e6-96231b3b80d8