Forums: Spam/Pending/Archived views should display topic titles

[SergeyBiryukov]

On Spam/Pending/Archived views, it's hard to tell which topic each reply belongs to, as there is no topic title:

• ​https://wordpress.org/support/view/spam/
• ​https://wordpress.org/support/view/pending/
• ​https://wordpress.org/support/view/archived/

The solution for the Replies page from #2002 could probably be reused.

[netweb]

Patch meta-2101.patch​ adds topic and reply headers based on #2002 for the spam, pending, and archive views:

[SergeyBiryukov]

The screenshots look good to me.

Noticed a couple of things:

• 'In forum: ' and ' topic: ' — spaces should be moved out of translatable string, we can't count on all translators to notice and keep them.
• The search template have a different styling for topic titles: ​https://ru.wordpress.org/support/search/test/, but that can wait for the theme revamp.

[coffee2code]

In 4225:

Forums Theme: Show context for posts listed in special views (e.g. spam/pending/archived).

• Always show linked forum name.
• Show topic name for topic posts.
• Show linked topic name for reply posts.

Props netweb, coffee2code.
Fixes #2101.

[SergeyBiryukov]

In 4768:

Support Theme: Show context for posts listed in special views (e.g. spam/pending/archived).

• Always show linked forum name.
• Show topic name for topic posts.
• Show linked topic name for reply posts.

Marges [4225] to the new theme.

Props netweb, coffee2code.
See #2101.