verify_special_jvm_flags operates only in debug builds and sanity checks the entries in the deprecated/obsoleted/expired/aliased tables. In addition it detects whether we have not yet removed the global variables for flags that are obsolete/expired, and issues a warning. In the latter case though it also returns false and causes the assertion to fail. This make it impossible to bump the JDK version without dealing with every flag en-masse.

We should issue the warnings but not fail the assert in these cases.

This need was flagged when we went to JDK 10 (see JDK-8173421) but not actioned.