Enables WebCache columns on OS X's task manager.
Enables WebCache columns on OS X's task manager.

TEST=Enabled the Task Manager context menu, opened, enabled columns and observed values that look reasonable.
BUG=16221

Review URL: http://codereview.chromium.org/243006

git-svn-id: http://src.chromium.org/svn/trunk/src@27270 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: 55a0c9f788240b1292f036a87deeb401310532f9
meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser