Previously, the "Remove" button in the asset blacklist floater removed
the last clicked-on entry only - even when selecting multiple rows (by
holding CTRL and clicking on entries).
This behaviour is unintuitive and tedious when trying to selectively
remove multiple entries.
The feature was requested in the group chat. Tested both removing a
single entry and multiple entries with two different avatars on Linux.
-Idle tick is now responsible for dispatching all pending sound sources, as such improves priority sorting.
-Added ui sound precache mechanisms (to fetch sounds without associated soundsources)
-Audio engine no logner available pre-login or upon disconnect, for simplicity.
-General cleanup to the audio engine/impl.
-Fixed some gAudiop calls that were lacking prerequisite null checks.
-Added 'isUpstreamOK' procuedure to LLAssetStorage to allow avoidance of making requests when there is no upstream host connection.
Cleans up some related code, probably looks nicer with space changes off.. though this is a pretty straightforward change.
Comments out code that still exists in xmls or might likely be added in future.
Each piece tested quite a bit.
Call AIFilePicker::create() instead of new AIFilePicker.
Renamed deleteMe() to kill() and bs_deleted to bs_killed.
Only default to auto destruct when created with create(true),
otherwise kill() has to be called explicitely.
Also upgrade the file picker filters with the new extensions found
in the orginal file picker code of Singularity.
Also improve AIFilePicker a bit: added hasFilename() and now
deleting the statemachine automatically by default: it's no longer
needed to call deleteMe from the callback.
