Reset counter() after test.

Otherwise, test will fail if repeated more than once: --gtest_repeat
Use ASan everywhere, if "use_asan" is true.

Have to disable flag "--no-undefined" on Linux.
Update libc++.

Compilation is broken until I update gperftools.
Waiting for responce on https://groups.google.com/forum/#!topic/google-perftools/1f9WN40SNJM