f/multishells: add `indexOfView` method, refactor `onSwapSubShell` and `onChangeSubShell`. this robusticizes these methods against `shells` array splicing when shells are deleted. - #65
f/multishells: add `indexOfView` method, refactor
`onSwapSubShell` and `onChangeSubShell`. this robusticizes these methods
against `shells` array splicing when shells are deleted.
- #65

athenalabs/acorn-player