They're betting the dev tools farm on Brackets, an open-source editor written in JS. To enable it to run on ChromeOS, FirefoxOS, or iOS, they need to have a better cloud filesystem story. Since git is the de facto format for sharing code across machines, they want to integrate git into Brackets. Then, you'd be able to write code on a device that doesn't have a traditional filesystem, locally caching changed resources and offloading the data persistence aspect to a service like BitBucket or GitHub.