Update header guards in test runner library to chromium style

BUG=331299
R=battre@chromium.org
NOTRY=true

Review URL: https://codereview.chromium.org/121113006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@242880 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 242880