Bound drop target layout values to left and right. am: 3c0f4c15 am: 781c68b2 am: 7d4c74b4

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Launcher3/+/18491881



Change-Id: Iffb3f1fb60f08b3396581f5d6550fa9b5b9ff741
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>