[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
diff --git a/lib/AST/DeclCXX.cpp b/lib/AST/DeclCXX.cpp
index eec2e9d..2f21e4c 100644
--- a/lib/AST/DeclCXX.cpp
+++ b/lib/AST/DeclCXX.cpp
@@ -1294,15 +1294,20 @@
 }
 
 CXXMethodDecl *
-CXXMethodDecl::getCorrespondingMethodInClass(const CXXRecordDecl *RD) {
+CXXMethodDecl::getCorrespondingMethodInClass(const CXXRecordDecl *RD,
+                                             bool MayBeBase) {
   if (this->getParent()->getCanonicalDecl() == RD->getCanonicalDecl())
     return this;
 
   // Lookup doesn't work for destructors, so handle them separately.
   if (isa<CXXDestructorDecl>(this)) {
     CXXMethodDecl *MD = RD->getDestructor();
-    if (MD && recursivelyOverrides(MD, this))
-      return MD;
+    if (MD) {
+      if (recursivelyOverrides(MD, this))
+        return MD;
+      if (MayBeBase && recursivelyOverrides(this, MD))
+        return MD;
+    }
     return NULL;
   }
 
@@ -1313,6 +1318,8 @@
       continue;
     if (recursivelyOverrides(MD, this))
       return MD;
+    if (MayBeBase && recursivelyOverrides(this, MD))
+      return MD;
   }
 
   for (CXXRecordDecl::base_class_const_iterator I = RD->bases_begin(),