cosnt BString& instead of const char* could potentially save copying the string,
although in most use cases, it will probably ammount to the same thing. It may
provide more flexibility later on, like for example when BString knows its
encoding or something similar. Removed superfluous second version of
AddOnClickRef().
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@36958 a95241bf-73f2-0310-859d-f6bbb57e9c96
908967a199