Conflict with comment_fragment.module

Problem/Motivation

On a site with comment_fragment.module working, any meta tags added by metatag.module will fail to render.

This is because comment_fragment.module changes the path to the comment to match the node path, and therefore this is being returned as TRUE from the _metatag_entity_is_page() function even though it isn't the page.

As metatag_entity_view() is only processed once per page and it already has a TRUE response, the node is not processed so no metatags are rendered.

Proposed resolution

If a comment is passed into _metatag_entity_is_page(), return FALSE straight away and ignore the comment entity. This let metatag_entity_view() run on the needed node entity and work successfully.

A patch is attached.