handle unavailability of LUTs when rendering

[mtbc]

What this PR does

Allows images to be rendered even when LUTs cannot be loaded, as in share contexts.

Testing this PR

Test that a user from wholly different groups as the owner can see in the full viewer images that have been shared with them.

Related reading

#4753
#5249
https://trello.com/c/sMxu4Rwi/

[pwalczysko]

Stacktrace:

• on your image (user-4) put a Fire LUT and Save.
• reverse the intensity of this LUT on the image and Save.
• create a Share with user-1
• login as user-1, find the Share
• select the thumb of the image, click Preview tab
• observe error (error attached to https://trello.com/c/sMxu4Rwi/73-bug-fix-shares (LUT_reverse_then_Share)

Happens with any Reverse intenstiy image in Shares. The presence of LUT in above workflow is not impotant.

SecurityViolation: exception ::omero::SecurityViolation
{
    serverStackTrace = ome.conditions.SecurityViolation: ome.model.display.ReverseIntensityContext:Id_8462 not contained in share
    at ome.security.sharing.SharingACLVoter.throwLoadViolation(SharingACLVoter.java:86)
    at ome.security.CompositeACLVoter.throwLoadViolation(CompositeACLVoter.java:91)
    at ome.security.ACLEventListener.onPostLoad(ACLEventListener.java:102)
...

[pwalczysko]

LUTs are being ignored by Shares:

• viewing a Shared image in Preveiw or Full Viewer as non-owner of the share you cannot apply a LUT (UI will allow this, but it will not show in the Full Viewer/Preveiw, instead the previously saved color (e.g. Red) will be displayed). If you change color to Yellow, this will be shown in Full Viewer. But if you select another LUT, the displayed color goes to "default" (e.g. Red).
• if you create and Save LUT Rnd settings on your image and then share it, the non-owner of the Share will not see the LUT- colored image in Full Viewer or Preview of the Share, instead, he/she will see the "default" color (e.g. red)

[pwalczysko]

The LUT and Reverse intensity workflows in Insight are fine.

[pwalczysko]

The widget "Open With" (next to the Full Viewer button) does not bring any results neither when you select Image Viewer, not OMERO.figure, nor IViewer.

[pwalczysko]

The Shares workflow works fine otherwise (did not get the e-mails about the Share creation and comments, but this might be because of the setup of eel (?)). Stopping testing for now.
@mtbc apparently can fix the #5250 (comment) reverse-intensity in shares crash.

[mtbc]

reverse-intensity in shares crash

should be fixed by 077210d

[jburel]

Few comments:

• Open with option on right-hand panel is introduced in Open with right panel #5217 and won't be included. The option should not be available for shares. To be fixed in Open with right panel #5217
• The Lut for share are no longer loaded, so it will always fall back to the color associated to the channel. The same is true is the lut is not recognized.
  This is a problem not related to share itself. https://trello.com/c/3jdIuUK2/77-channels-controls-out-of-synch. We will probably need a new method on rendering engine isLutLoaded to completely disable the functionality

[pwalczysko]

Also reverse intensity LUTed image in Shares gives now a fallback on the color. Tested both LUTs and reverse intensities. No crashes. This is a workable solution FMPOV.

[jburel]

The thumbnails will be out of synch when viewing the image with Lut in a share

[jburel]

Will indicate in the announcement that Lut not available in share is a known limitation
that could lead to thumbnail/main viewer being out of synch

[mtbc]

👍 Related comment at https://trello.com/c/SrcTVbw3/135-lut-improvements#comment-58f481c96b7c63921664b45e