Merge "Add the DefaultItemAnimator, without change animations" into sc-dev am: d9abe11b92 am: 5bb331df92 am: 0c47a6589b

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Launcher3/+/14736372

Change-Id: I0b0dbb33896925949976cfca8151a73753cdf1a6