[analyzer] Allow pointers escape through calls containing callback args.

(Since we don't have a generic pointer escape callback, modify
ExprEngineCallAndReturn as well as the malloc checker.)

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@156134 91177308-0d34-0410-b5e6-96231b3b80d8
10 files changed