As bug 577170 described, a chooser dialog needs to be implemented on Chrome Apps so that WebBluetooth API can be used there. Since the chooser content view is the same for WebBluetooth on desktop and Chrome Apps, it is better to pull it out of ChooserBubbleUiViewDelegate so that it can be reused and thus reduce code redundancy.
Comment 1 by bugdroid1@chromium.org
, Jun 10 2016