Older Oembed post meta data not being removed on Post Update

[aware]

If you have a post that has an oembed link within it, then you replace said oembed link with a new link.

The original oembed link's oembed_md5 post meta will still exist even though the oembed link is no longer within the post.

I did not test a scenario to see if you simply remove the link entirely from the post with out replacing it with another one if it is cleared out. My assumption is that it isn't cleared out.

[SergeyBiryukov]

Related: #14759

[obenland]

Embed cache gets deleted on 'save_post'. Please reopen if the issue still occurs for you.