Merge "Support swiping in both directions for trackpad back gesture" into udc-dev am: e7020d59 am: 20883310

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/21616356



Change-Id: I2f7b407a2302ee93aa1e6207ab366de26f7dacc2
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>