Merge "Fix rounded corners for shortcut & generated preview shadow box" into sc-dev am: bf60673bbb am: c2675adef5

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Launcher3/+/15098570

Change-Id: I5c7ba53f86e8edac856c8337311c2b3c7c4eb22f