Update third-party hash for libmbfl cmake fix

Summary: See: https://github.com/hhvm/hhvm-third-party/commit/1d387ce2a33fc75d25c7ee3318537296387d8799

Reviewed By: @paulbiss

Differential Revision: D1747030

Signature: t1:1747030:1418864344:44cf2ea827cccd2c2fd4a926352855ce7bc975b9
Fix Memcached::setOption for OPT_LIBKETAMA_COMPATIBLE

Summary: The current implementation is missing an if-statement which causes
the option to be unset even when a truthy value is passed in. The comment
directly above this block describes the correct behavior. See the original PHP
implementation for reference: http://goo.gl/7p7WqP. A new constant
Memcached::DISTRIBUTION_CONSISTENT_KETAMA is added for the sake of testing.

Closes https://github.com/facebook/hhvm/pull/4364

Reviewed By: @paulbiss

Differential Revision: D1710109

Signature: t1:1710109:1418880558:9a97113ad941927c06ca0ed8389f2208b18eca86
Actually get the realpath first thing when searching for a file.

Summary: D1729338 fixed a subtle bug, but not completely. We didn't handle the case where
the test runner was run in the exact same directory as the test in question. If we
did, it would still come in as `.` if `dirname()` was used beforehand, which is
probably not desired behavior. So move the call to `realpath()` to before the
`while()` loop and all cases should now be handled.

{sync, type="child", parent="internal", parentrevid="1742941", parentrevfbid="866765913387291", parentdiffid="5964829"}

Reviewed By: @paulbiss

Differential Revision: D1742941

Signature: t1:1742941:1418878079:1499d0d009589f7a47a1f1a04e08619c2813b673