Code review comment for lp://staging/~fboucault/music-app/startup_time

This is the super old branch from before [0], you can see the discussions we had. The preferred solution in that was to load the selected tab and then the others in async, but not unload. As the flicker was a large distraction to the user, note that the branch was on a much older codebase (before moving to GridView etc).

0 - https://code.launchpad.net/~ahayzen/music-app/refactor-async-loader-pages/+merge/248477