[analyzer] NFC: Assert that our fix for noreturn destructors keeps working.

Massive false positives were known to be caused by continuing the analysis
after a destructor with a noreturn attribute has been executed in the program
but not modeled in the analyzer due to being missing in the CFG.

Now that work is being done on enabling the modeling of temporary constructors
and destructors in the CFG, we need to make sure that the heuristic that
suppresses these false positives keeps working when such modeling is disabled.
In particular, different code paths open up when the corresponding constructor
is being inlined during analysis.

Differential Revision: https://reviews.llvm.org/D42779

llvm-svn: 324802