Remove unused runtime setting experimentalnotificationsenabled
Remove unused runtime setting experimentalnotificationsenabled

This setting existed in WebKit but Chromium never changed it from its default value. We're removing all such unchanging settings in Blink, along with their associated code.

R=abarth@chromium.org
BUG=226711

Review URL: https://codereview.chromium.org/13908003

git-svn-id: bf5cd6ccde378db821296732a091cfbcf5285fbd@147936 bbb929c8-8fbe-4397-9dbb-9b2b20218538

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