[analyzer] Don't communicate evaluation failures through memregion hierarchy.

We use CXXTempObjectRegion exclusively as a bailout value for construction
targets when we are unable to find the correct construction region.
Sometimes it works correctly, but rather accidentally than intentionally.

Now that we want to increase the amount of situations where it works correctly,
the first step is to introduce a different way of communicating our failure
to find the correct construction region. EvalCallOptions are introduced
for this purpose.

For now EvalCallOptions are communicating two kinds of problems:
- We have been completely unable to find the correct construction site.
- We have found the construction site correctly, and there's more than one of
  them (i.e. array construction which we currently don't support).

Accidentally find and fix a test in which the new approach to communicating
failures produces better results.

Differential Revision: https://reviews.llvm.org/D42457

llvm-svn: 324018