Fix undefined behavior when compiling in C++14 due to sized operator delete

being called with the wrong size: convert CGFunctionInfo to use TrailingObjects
and ask TrailingObjects to provide a working 'operator delete' for us.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@260181 91177308-0d34-0410-b5e6-96231b3b80d8