[analyzer] Correctly devirtualize virtual method calls in constructors.

This is the other half of C++11 [class.cdtor]p4 (the destructor side
was added in r161915). This also fixes an issue with post-call checks
where the 'this' value was already being cleaned out of the state, thus
being omitted from a reconstructed CXXConstructorCall.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@161981 91177308-0d34-0410-b5e6-96231b3b80d8
6 files changed