Bug 1032651 - [Gaia] CMAS on/off toggle in Settings

- Two toggles, CB and CMAS
- when CB off, CMAS is also off and disabled
- When CB on, user can turn on/off the CMAS
- When CB on, CMAS state will be retained to the state before CB off.
- add marionette test
- make CMAS totally count on CBS
Merge pull request #22264 from gasolin/issue-1032651

Bug 1032651 - [Gaia] CMAS on/off toggle in Settings, r=arthur