Merge "simpleperf: Remove stack and register fields for samples without userspace stack" am: c542a57db1

Original change: https://android-review.googlesource.com/c/platform/system/extras/+/2551055

Change-Id: Ib32f9d7ed39e27848a5b049ceaa07245a163b3dc
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>