Fix a bug where we were trying to reconstruct ivars of ObjC types from the...

Fix a bug where we were trying to reconstruct ivars of ObjC types from the runtime in "expression parser mode"

The expression parser mode allows UnknownAnyTy to make it all the way through, but that is bad for ivars because it means type layout fails horribly (as in, clang crashes)

This patch fixes the issue by using the "variables view mode", which masks UnknownAnyTy as empty-type, and pointer-to UnknownAnyTy as void*

This, in turn, allows LLDB to properly reconstruct ivars of IMP type in ObjC type - as per accompanying test case

Fixes rdar://21471326

llvm-svn: 240677