17.12 VS hang on solution close

[JanKrivanek]

Context

microsoft.visualstudio.projectservices.dll!Microsoft.VisualStudio.ProjectServices.DesignTimeBuildService.SolutionClosedEventHandler
https://prism.vsdata.io/failure/?query=ch%3Drelease%20r%3D17.12&eventType=hang&failureHash=cdfda8b0-fdb8-70cd-57c9-ad606708a21f
116 hits in the wild - ranks as top 14 hang

It seems related to previously fixed case: #10709 (comment) (thoug it seems slightly different)

FYI @davkean (pointed this case out)

[JanKrivanek]

It looks like we lost information about worker node shutdown and hence keep waiting for it (nodeId is 2 - pointing out to OutOfProcNode).
Otherwise the submission is completed with build cancelled result - so this is distinct from #10709

[JanKrivanek]

Through ComponentHost DI I got to the PID of the out of proc node that the BuildManager was waiting for - its: 10396:

From the case ETL

I can see that that that process did not terminate:

So it might be possible that shutdown request wasn't even properly sent out