Improve LLDB's embedded C++ demangler by addressing the following two issues:
1) Preserve ref qualification state in a local variable while parsing a nested name. Previously, the state was recorded in the shared db reference and could therefore be overwritten when parsing multiple levels of nested names (e.g.: when a qualified name has qualified template args.)
2) Address an off-by-one error when testing whether or not a thunk is non-virtual. This resulted in the demangled identifying all thunks as non-virtual.
llvm-svn: 213591