Merge "Fix NPE if draging again while animating" into tm-dev am: a876e7b2 am: 225f5489

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/18570244



Change-Id: If9ea6656a6b1683a84d793a32c451296feed30e4
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>