BUG: FS Plate ROI analysis

[rkferguson]

Testing using OMERO.insight-5.0.0-alpha4-388-c2c93d6-dirty-ice33-b304-mac on gretzky user-3 read-annotate-1

ROI drawing and refreshing of intensity data and graphs first appeared to be working well - changes showing in real time - and then started running into delays of up to 25 seconds to update. Seemed to be worse the further into the plate the cell occurred.
Continued to deteriorate until waiting a minute or more for updates.

Log showed errors.

Quit and logged back in.

Started with A1 (first well)
Draw line ROI - 20 seconds before graph displayed
Then updates real time
Second line ROI - initial update immediate and real time with movement of line

Delay appears to get worse the further into the plate you view.

Closed A1 and opened F6 (about middle of plate)
Draw line ROI - no graph displayed after 4 minutes of waiting
Clicked on manager tab then back on graph pane and graph appeared
Error displayed in log
Move line - update to graph takes 20 seconds
Thereafter changes in graph pane with movement are reflected in real time
Draw second line - changes in graph pane reflected in realtime

Closed F6 and opened P11 (last well)
Switching between manager and graph pane every 20 seconds or so
Graph appears at 2 minutes.
Move line - graph update takes 1 minute
Move again takes 38 seconds to update
And 38 - 40 seconds for all subsequent updates after moves.
Never achieves real-time updates.

Log attached.

[dlindner]

Fixed with ​https://github.com/openmicroscopy/openmicroscopy/pull/4256