Only showing notification when a restart is needed. Partial fix to 5168.

BUG=chromium-os:5168
TEST=Manual - use devserver to install update and verify notification
appears to restart after update is installed with no other notifications.

Review URL: http://codereview.chromium.org/3157018

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@56616 0039d316-1c4b-4281-b951-d872f2087c98
2 files changed