This patch makes LLDB able to retrieve proper values for function arguments and local variables stored in PDB relative to VFRAME register.
Patch contains retrieval of corresponding FPO table entries from PDB and a generic translator from FPO programs to DWARF expressions to get correct VFRAME value.
Patch also improves variables-locations.test and makes this test passable on x86.
Related to D53086
Why do we change the return value here?