[analyzer] Split the MallocChecker into two versions - pessimistic and
optimistic.

TODO: actually implement the pessimistic version of the checker. Ex: it
needs to assume that any function that takes a pointer might free it.

The optimistic version relies on annotations to tell us which functions
can free the pointer.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@150111 91177308-0d34-0410-b5e6-96231b3b80d8
4 files changed