Merge "Update CachingWidgetPreviewLoaderTest members to be non-static. These classes are stubbed by roboelectric so they cannot be static" into sc-dev am: 8fc2d80a32 am: 37f1fbf7ab

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Launcher3/+/15226443

Change-Id: I44d3b93854744b1a7f4fc2bea681bd92eeae0804