Merge "Reduce <CallStack.h> namespace pollution." into main am: d6ccb0b1d9 am: f795d2bf16

Original change: https://android-review.googlesource.com/c/platform/system/core/+/2974871

Change-Id: I7a54d57b943aedbf5ae3b577e43497b0cc9676e2
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>