[dev] Horde_History::removeByParent() block size

[Thomas Jarosch]

Hi,

I just noticed the Horde_History::removeByParent() function
deletes from the history database in blocks of 100 entries each.

The removeByNames() function, also used for deleting entries,
sends all entries to the database in one go.

@MMS: What's the reason for splitting up the request?

According to git, the split up was in there since the initial commit.

I can imagine databases also have a limit for the length of the query string 
(similar to the number of UIDs you can send to an IMAP server in one go).

If that's the case, we should move the 'split logic' to removeByNames()
since it's the workhorse of removeByParent() and a public API function.

Cheers,
Thomas