Added sound resource for volume up/down.

BUG=225886
R=thakis@chromium.org, xiyuan@chromium.org

Review URL: https://codereview.chromium.org/104653014

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@239822 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 239822