Fix perf regression introduced with a bad fix for OS#17417473

Author: paolosevMSFT

lib/Backend/GlobOpt.cpp

@@ -14274,7 +14274,7 @@ GlobOpt::OptIsInvariant(Sym *sym, BasicBlock *block, Loop *loop, Value *srcVal,
     }
     else if (sym->IsPropertySym())
     {
-        if (!loop->landingPad->globOptData.liveFields->Test(sym->AsPropertySym()->m_stackSym->m_id))
+        if (!loop->landingPad->globOptData.liveVarSyms->Test(sym->AsPropertySym()->m_stackSym->m_id))
         {
             return false;
         }