Fix instrumented libcap2 build.

BUG=313751
TBR=glider@chromium.org

Review URL: https://codereview.chromium.org/161073002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@250785 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 250785