Bug 838622 - [Dialer] USSD unit tests are failing; r=arcturus

nit

Fixes handle_call by arcturus
Merge pull request #8107 from ferjm/bug838622

Bug 838622 - [Dialer] USSD unit tests are failing; r=arcturus
Bug 837071 - [Contacts] Not consistent layout for "No Content" screens in Call Log, SMS and Contacts