Add an activity for wallet card carousel screen.

The WalletActivity initializes a WalletScreenController to query the
wallet cards and present on the content view.
The next step is to launch the new activity from QuickAccessWalletTile.

Test: manually test on deivce
Test: atest
Bug: b/182964813
Change-Id: Idbf0918e111db0d00f3b60b8c26b968c961df202