[modules] When emitting an update record containing the body of a destructor,
also emit the updated 'operator delete' looked up for that destructor. Switch
from UpdateDecl to an actual update record when this happens due to implicitly
defining a special member function and unify this code path and the one for
instantiating a function definition.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@215132 91177308-0d34-0410-b5e6-96231b3b80d8
Debug info: Use record layout to find vbase offsets instead of vtables

This fixes an assertion when generating full debug info in the MS ABI
for classes with virtual bases.

Fixes PR20579.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@215137 91177308-0d34-0410-b5e6-96231b3b80d8