Stop prefix: filter from searching redirects

Even though it is named after regular prefix searches, we don't want it
to search redirects.  Mostly, we don't want it to to that because people
don't expect it to.  Additionally, it is _very_ hard to figure out what
is going on because the prefix filter doesn't get highlighted.

Bug:  65232
Change-Id: I8c155f189c068631828faa59e1a84610eeba68a5
Update load test script

This should cause it to be even less artificially bursty

Change-Id: I794890b96c99c5ba20b0b7c45b1ee4215433f7bb
Merge "Update load test script"