Map OOM breaks generated by inspector to DebugEvent.OOM.
This avoids generating unintentional DebugEvent.Break events.

Also be more future-proof in event categorization.

On a related note, this CL also fixes a DCHECK in
Runtime::GetFrameDetails.

The receiver needs to be grabbed from the inlined frame, not
the outer optimized frame. Optimized frames only provide the
receiver on a best-effort basis.

BUG=v8:5950

Review-Url: https://codereview.chromium.org/2696173002
Cr-Commit-Position: refs/heads/master@{#43244}