| This folder contains the functionality for tracking browser app instances, that | |
| is, tabs opened in Chrome (and are part of the tabbed browser) that are | |
| logically considered part of an app. This functionality is only used on | |
| ChromeOS, which has "tabbed apps" as part of its UX where URLs in the browser | |
| can have first-class OS UX, e.g. icons in the shelf and launcher. This code | |
| is required to ensure those UX work correctly. |