Get rid of anonymous table* wrappers when they are no longer needed.

When a renderer is removed, don't just see if an anonymous parent
should be destroyed, but keep looking further up in the ancestry
as well.

BUG=389129

Review URL: https://codereview.chromium.org/540453003

git-svn-id: svn://svn.chromium.org/blink/trunk@182082 bbb929c8-8fbe-4397-9dbb-9b2b20218538