If a custom token is added but the balance update fails, it is never shown in the asset list.

To Reproduce (REQUIRED)

1. Add a custom token with an address that will always fail when you check the balance
   • I used the address 0xC011A72400E58ecD99Ee497CF89E3775d4bd732F, which is the old SNX address. 18 decimals, though that doesn't matter in this case.
2. Check the Assets tab of the Home screen

Expected behavior
The token should be present in the asset list, regardless of whether the balance update succeeded or not