This change has introduced a dependency from Core -> clang Driver (due to #include "clang/Driver/Driver.h" in ModuleList.cpp). Can you please try to find a way to remove this dependency?
This is implementing Jim's suggestions in http://lists.llvm.org/pipermail/lldb-commits/Week-of-Mon-20180521/041010.html .
This certainly makes sense from a logical perspective, but I'm not sure whether this addresses Zachary's concerns. Let me know what you think.