Distribution:+bugs timeouts

We've improved the performance of the search, but that has just reduced the frequency of timeouts, it still times out.

OOPS-1868M2484

https://bugs.launchpad.net/ubuntu/+bugs?field.searchtext=grub_xputs&orderby=-importance&search=Search&field.status:list=NEW&field.status:list=INCOMPLETE_WITH_RESPONSE&field.status:list=INCOMPLETE_WITHOUT_RESPONSE&field.status:list=CONFIRMED&field.status:list=TRIAGED&field.status:list=INPROGRESS&field.status:list=FIXCOMMITTED&field.assignee=&field.bug_reporter=&field.omit_dupes=on&field.has_patch=&field.has_no_package=

There are two repeated queries that combine to use up 3.5 seconds of time:

2 16 1817 113 1704 SQL-launchpad-main-slave
SELECT COUNT(*)
FROM BugTask
JOIN Bug ON BugTask.bug = Bug.id
WHERE Bug.id = BugTask.bug
  AND BugTask.distroseries = $INT
  AND ((BugTask.status = $INT)
       OR (BugTask.status = $INT)
       OR (BugTask.status = $INT)
       OR (BugTask.status = $INT)
       OR (BugTask.status = $INT)
       OR (BugTask.status = $INT))
  AND Bug.duplicateof IS NULL
  AND (Bug.private = FALSE
       OR EXISTS
         (SELECT BugSubscription.bug
          FROM BugSubscription,
               TeamParticipation
          WHERE TeamParticipation.person = $INT
            AND TeamParticipation.team = BugSubscription.person
            AND BugSubscription.bug = Bug.id
          UNION SELECT BugTask.bug
          FROM BugTask,
               TeamParticipation
          WHERE TeamParticipation.person = $INT
            AND TeamParticipation.team = BugTask.assignee
            AND BugTask.bug = Bug.id))

4 14 2305 164 2141 SQL-launchpad-main-slave
SELECT COUNT(*)
FROM BugTask
JOIN Bug ON BugTask.bug = Bug.id
WHERE Bug.id = BugTask.bug
  AND ((BugTask.status = $INT)
       OR (BugTask.status = $INT)
       OR (BugTask.status = $INT)
       OR (BugTask.status = $INT)
       OR (BugTask.status = $INT)
       OR (BugTask.status = $INT))
  AND BugTask.milestone = $INT
  AND Bug.duplicateof IS NULL
  AND (Bug.private = FALSE
       OR EXISTS
         (SELECT BugSubscription.bug
          FROM BugSubscription,
               TeamParticipation
          WHERE TeamParticipation.person = $INT
            AND TeamParticipation.team = BugSubscription.person
            AND BugSubscription.bug = Bug.id
          UNION SELECT BugTask.bug
          FROM BugTask,
               TeamParticipation
          WHERE TeamParticipation.person = $INT
            AND TeamParticipation.team = BugTask.assignee
            AND BugTask.bug = Bug.id))