Do not duplicate profiles on switching panels after ProfilesPanel was cleared

BUG=267517
R=alph@chromium.org

Review URL: https://codereview.chromium.org/22407003

git-svn-id: svn://svn.chromium.org/blink/trunk@155674 bbb929c8-8fbe-4397-9dbb-9b2b20218538