Remove FIXME about asserting on the end iterator
Remove FIXME about asserting on the end iterator

After machine block placement, MBBs may not have terminators, and it is
appropriate to check for the end iterator here. We can fold the check
into the next if, as well. This look is really just looking for BBs that
end in CATCHRET.

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@278350 91177308-0d34-0410-b5e6-96231b3b80d8

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