Add in ASSERT to avoid NULL point dereference.

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@7491 6f19259b-4bc3-4df7-8a09-765794883524

MdeModulePkg/Universal/SetupBrowserDxe/IfrParse.c

@@ -1740,6 +1740,8 @@ ParseOpCodes (
             if (EFI_ERROR (Status)) {
               return Status;
             }
+
+            ASSERT (CurrentExpression != NULL);
             if (CurrentExpression->Result.Type != EFI_IFR_TYPE_BOOLEAN) {
               return EFI_INVALID_PARAMETER;
             }