Merge "Make BackEvent#getTouchX and BackEvent#getTouchY floats." into tm-dev am: e16244c3 am: 11c1bbb2 am: 2e4361c3

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/17650054



Change-Id: I82bdd18d838ba39352471bf2a064b6ac1d16de9e
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>