Added process title to Process Monitor Sample Extension

Screenshot: http://i.imgur.com/6hrYh1c.png

Review URL: https://codereview.chromium.org/191143002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@255936 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 255936