Wallet screen UI Polish:

1. update the fading effect for action button.
2. the action button will depend on whether the card above it has the
second line label.
3. update the options menu item background to 1 shade lighter grey.

Test: manual, see demo:
https: //drive.google.com/file/d/1TLc6t1Ola6G_QiU0yadWdh1nLbQnEJ7g/view?usp=sharing&resourcekey=0-f1qKR8nLjvo0VrtLqKBE9w
Bug: 190760488
Bug: 190531125
Change-Id: I012694e9ff0a252f6ce918043f6bf7dcd01ba97e