[PATCH] ignore --disable-free in clang when leak detection is enabled

[Kostya Serebryany]

  >> by placing their pointers into a global root somehow
  That would be easy and will solve the problem.
  We just need to create a global  "vector<void *> *globally_live_objects = new vector<void *>;" or some such
  and push all live objects there (there are very few of those).
  Suggestions where to put such vector?
  It's a bit ugly for my taste though.

  >>  I'd hate to have to a full clean build with a new -D flag
  The regular mode of running clang under lsan would be to run it as a part of asan build.
  But I agree with this concern in general.

http://llvm-reviews.chandlerc.com/D2475