Update the Multiple backstack recipe to use the new [view model store entryDecorator overload](https://android-review.googlesource.com/c/platform/frameworks/support/+/4043653) when it drops. This resolves the issue where view models of previousEntries are cleared even though they are not popped.
Update the Multiple backstack recipe to use the new view model store entryDecorator overload when it drops.
This resolves the issue where view models of previousEntries are cleared even though they are not popped.