This is part of a longer term clean up (Issue 681867). Tab class has an ivar of type id<StoreKitLauncher> that can be turned into a TabHelper object and access all information it needs via WebState.
However, NativeAppNavigationController needs to launch a SKStoreProductViewController UI which is currently handled by -[Tab openAppStore:]. This method needs to be removed from Tab and handled differently.
Comment 1 by pkl@chromium.org
, Mar 7 2017