option that works with all object container formats.
Now that clang modules/PCH are object containers this option is useful to
to construct pipes like
llvm-objdump -raw-clang-ast foo.pcm | llvm-bcanalyzer -
to inspect the AST contents in a PCH container.
Will be tested via clang.
Belatedly addresses review feedback for r233390.
llvm-svn: 241659