Merge "documenting optimized flash super" into main am: a3b232c30c am: b5bb46cd25 am: 11481b3cfe

Original change: https://android-review.googlesource.com/c/platform/system/core/+/2725774

Change-Id: I9e3e8793ad599a091f49c613dc0fb7a686143133
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>