[tooling] Fix missing inline keyworkd, breaking build bot.

Summary:
The missing keyword "inline" is causing some buildbot to fail.
The symbol is not available.

see: http://lab.llvm.org:8011/builders/clang-ppc64be-linux-multistage/builds/2281/

Reviewers: rnk

Subscribers: cfe-commits, klimek

Differential Revision: http://reviews.llvm.org/D20180

llvm-svn: 269224