Missing stream_title_changed events

[kingosticks]

As part of trying to improve the support for stream titles in Musicbox-Webclient I see that Mopidy only emits the stream_title_changed event if the 'organization' tag is present.

mopidy/mopidy/core/actor.py

Lines 134 to 137 in 99d8a21

	# TODO: this limits us to only streams that set organization, this is
	# a hack to make sure we don't emit stream title changes for plain
	# tracks. We need a better way to decide if something is a stream.
	if 'title' in tags and tags['title'] and 'organization' in tags:

Sadly, this tag isn't set for some of the streams I tried. This issue is closely related to, and would be fixed by, #270 and #1138 but maybe could be solved without those. One improvement might be to suppress the title tag if the tack has a non-zero duration instead?

[kingosticks]

Or only suppress it when the title matches the current track name. That actually sounds quite good to me.