Improve FakeDeliveryService to better differentiate sessions and background activities

[bidetofevil]

Goal

Testing

Release Notes

WHAT:
WHY:
WHO:

[bidetofevil]

• #855
• #854
• #846 👈
• master

This stack of pull requests is managed by Graphite. Learn more about stacking.

Join @bidetofevil and the rest of your teammates on Graphite

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 80.91%. Comparing base (248a719) to head (6f043d8).

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #846      +/-   ##
==========================================
+ Coverage   80.90%   80.91%   +0.01%     
==========================================
  Files         423      423              
  Lines       11456    11456              
  Branches     1746     1746              
==========================================
+ Hits         9268     9270       +2     
  Misses       1432     1432              
+ Partials      756      754       -2     

see 4 files with indirect coverage changes