[domain availability] Ignore disabled ivars during CodeGen

Fix a bug where disabled ivars weren't being ignored during codegen for
method .cxx_destruct and ivar bitmap layout.

rdar://165722993

Author: ahatanaka

clang/lib/CodeGen/CGObjC.cpp

@@ -1722,6 +1722,9 @@ static void emitCXXDestructMethod(CodeGenFunction &CGF,
   const ObjCInterfaceDecl *iface = impl->getClassInterface();
   for (const ObjCIvarDecl *ivar = iface->all_declared_ivar_begin();
        ivar; ivar = ivar->getNextIvar()) {
+    if (CGF.CGM.getContext().hasUnavailableFeature(ivar))
+      continue;
+
     QualType type = ivar->getType();
 
     // Check whether the ivar is a destructible type.

clang/lib/CodeGen/CGObjCMac.cpp

@@ -5488,7 +5488,8 @@ CGObjCCommonMac::BuildIvarLayout(const ObjCImplementationDecl *OMD,
   if (CGM.getLangOpts().getGC() == LangOptions::NonGC) {
     for (const ObjCIvarDecl *IVD = OI->all_declared_ivar_begin(); IVD;
          IVD = IVD->getNextIvar())
-      ivars.push_back(IVD);
+      if (!CGM.getContext().hasUnavailableFeature(IVD))
+        ivars.push_back(IVD);
 
     if (isNonFragileABI()) {
       baseOffset = beginOffset; // InstanceStart