fix a bug in SourceManager::getInstantiationLocSlowCase, where
we'd add an offset from the spelling location space to the 
instantiation location, which doesn't make sense and would
lead up to the text diagnostics crashing when presented with
non-sensical locations.

This fixes rdar://7597492, a crash on 255.vortex.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@96004 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed