performance.mark/measure for the extensionHost

[vaclavHala]

Recently I found out it is possible to use the performance.mark() and performance.measure() APIs inside webview to get user timings in the Performance tab of the devtools - very useful.

Sadly the same thing does not seem to work when I call the performance inside my main extension code. The Timings swimlane is completely missing so my calls into the perf API seem to be ignored. I guess this is because of the multi-process architecture of vscode where the extension host is isolated from the main somehow? Is there some trick I could use to get the timings also from extension host? It'd be fine even if the process has some manual steps, like say exporting the performance snapshot into some file and then importing it back into devtools - I'm not too familiar with the devtools so I don't know what options there are really