NotFound is obviously wrong, and this change stops viewer 3.2.2 (and v probably earlier) complaining in the log about missing textures that are actually present.
We still return PartialContent even if the range requested is a superset of the data range as per httpd's behaviour
https://issues.apache.org/bugzilla/show_bug.cgi?id=51878
Viewer 3.2.2 and very probably earlier appear happy with this.
Whether fixing this NotFound bug has any practical effect apart from resolve viewer log messages is unknown.
This prevents a possible race condition where the client would be told all baked textures had updated before they were in the asset service.
The client would then trigger a set appearance which, after a delay, would send the avatar appearance out to other clients.
The race condition seems unlikely because of this delay but it's still possible.
Might help with grey avatar appearances.
Enabling this by setting Cap_FetchInventoryDescendents2 = "localhost" in the [ClientStack.LindenCaps] section of OpenSim.ini downloads inventory via http rather than udp in later viewers.
Leaving them at UUID.Zero meant that when a viewer 2 logged into a region that had been freshly created, it received UUID.Zero for these textures, and hence display the land as plain white.
On a simulator restart, the problem would go away since when the database adapators loaded the new region settings, RegionSettings itself has code to use default textures instead of UUID.Zero.
This commit resolves the problem by saving the default texture UUIDs instead of Zero.
However, we currently have to do this in a roundabout way by resaving once the RegionSettings have been created by the database for the first time. This needless complexity should be addressed.
This change will also have the effect of replacing any existing UUID.Zero terrain textures with the default ones.
However, this shouldn't have any effect since the UUID.Zeros were already being replaced in memory with those same UUIDs.
Justin Clark-Casey (justincc)