Make these methods non-inline.

Change-Id: I0b24e34dec6c452659b224b45a6849dafe708c3b
Apply pimpl to Fraction.

Change-Id: I60eb597a6374b807b2264af6d5841a42e9b1c0f3
Build fix on Linux.

Change-Id: Iea96991a3bef08c17a8a0cbc347408dadc0061af
Build fix.

Change-Id: Ifa6775384993900980c93df88162143aa7ac0a08
Build fix on Windows

Change-Id: I5c24856bfe48646bc0e9cd00f0849a5db12dfef2