experiment: gcdump reading

[bruno-garcia]

What if we read the gcdump, then augment the low memory event with the top offending types

Not sure how much memory would take to do this in-memory in a process that just triggered a memory dump for being out of memory It probably needs to be done on a separate process. Or only on restart?

Or on the server, at ingestion time. Considering the mess it would be to get this into the SDK (I had to hack a lot to get it to run) it might be better doing this as a stand alone library, and load it during ingestion time in Sentry when processing gcdump files.

Required hacks on perfview too:

• https://github.com/microsoft/perfview/pull/2228