Make sure $found actually contains values

I had one key where the value was null on my local machine (likely odd test
data), which caused a warning when trying to array_merge a couple lines down:
Warning: array_merge(): Argument #3 is not an array in includes/Formatter/RecentChangesQuery.php on line 90

Change-Id: I4af443446b030d391cf4daeb1895e0fa9f875289
(bug 71619) Remove duplicate "created topic" item from watchlist

Wasn't properly collapsing created topic entries; used old "new-post" action
name.

Bug: 71619
Change-Id: If901d5216807984fe836784d5e573470c0aa8b1a
Merge "Make sure $found actually contains values"
Merge "(bug 71619) Remove duplicate "created topic" item from watchlist"