DWO/DWP should not be indexed directly.
Instead, the corresponding base file should be used.
This diff adds an assert to DWARFCompileUnit::Index
and adjusts the methods
SymbolFileDWARF::FindCompleteObjCDefinitionTypeForDIE,
SymbolFileDWARF::GetObjCMethodDIEOffsets accordingly.
Differential revision: https://reviews.llvm.org/D39825
llvm-svn: 318554