The test optnone-simple-functions.cpp added in D97668 fails on macOS.
os.path.exists raises an exception because we pass it None. Guard against this.
Related revision: https://reviews.llvm.org/D97668
Add DebuggerControllerBase and DefaultController to Dexter
implements a new architecture that supports new and novel ways of running
a debugger under dexter.
Current implementation adds the original default behaviour via the new
architecture via the DefaultController, this should have NFC.
Reviewers: Orlando
Differential Revision: https://reviews.llvm.org/D76926