Fix funky javadoc

Using @link for the first word of a @throws line is redundant and
generates strange HTML where the row appears twice.

See for example:
    http://developer.android.com/reference/android/net/VpnService.Builder.html#addAllowedApplication%28java.lang.String%29

Change-Id: I9c0bbe9156d292eb6f0e2e2ccb6dbcfef95bc312