[PM] Wire up support for the bounds checking sanitizer with the new PM.

Not much interesting here. Mostly wiring things together.

One thing worth noting is that the approach is substantially different
from the old PM. Here, the -O0 case works fundamentally differently in
that we just directly build the pipeline without any callbacks or other
cruft. In some ways, this is nice and clean. However, I don't like that
it causes the sanitizers to be enabled with different changes at
different times. =/ Suggestions for a better way to do this are welcome.

Differential Revision: https://reviews.llvm.org/D39085

llvm-svn: 318131