Don't try and install extensions when --enable-extensions isn't
on.

Also, pop up a dialog telling the user they probably forgot to
turn on the flag.

Review URL: http://codereview.chromium.org/99295

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@15116 0039d316-1c4b-4281-b951-d872f2087c98
1 file changed