Clarify in comment Perfetto binary size flags. am: dce85ffe78 am: 74ec190bc1

Original change: https://android-review.googlesource.com/c/platform/packages/modules/Connectivity/+/2528602

Change-Id: If030a71da195ba426515c0bc09c11590b942b3be
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>