Fix up scoping in a few tests (and delete one that validates unnecessary behavior).

Most of this is just tests that were silently succeeding in spite of
schema changes I made over a year ago. Cleaning them up as they lead to
failures in a change I'm working on/will come soon.

test/DebugInfo/2010-01-19-DbgScope.ll was removed as it tested miscoping
where a DebugLoc described a location not in the current function. The
test case doesn't describe why this is a valid situation and should be
supported, so I'm removing it and shortly going to commit changes that
make this firmly unsupported/assert-fail.