RFR: 8233214: Remove runtime code not needed with CMS removed

Fri Oct 9 13:10:13 UTC 2020

On Fri, 9 Oct 2020 11:27:00 GMT, Coleen Phillimore <coleenp at openjdk.org> wrote:

> This change removes CMS code left over for ClassLoaderData walking.
> Tested with Oracle platforms tier1 and built shenandoah with no errors.

Good sans the "YC/CMS" comment

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Marked as reviewed by tschatzl (Reviewer).

PR: https://git.openjdk.java.net/jdk/pull/574