Fixing ModelPreload cancelling existing load am: 57d4f748b8 am: 90c6b6a19f am: ce5d91df28 am: 9e7ba604b7

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Launcher3/+/15820555

Change-Id: Ie8cc033702bee1b8310c0ca241618851195351f7