Merge "Prevent swipe-to-dismiss conversation header" into rvc-dev am: e91a027e am: 891fba38 am: e0de71fb am: dd6f4585

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/11820083

Change-Id: Idf95ec85701470764c3c1b00fbdb3e51aa882381