Ensure window container level is set on underlying window

[bbirman]

No description provided.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 63.59%. Comparing base (33923fa) to head (65fb98d).
Report is 1221 commits behind head on dev.

Additional details and impacted files

@@           Coverage Diff            @@
##           dev    #3776       +/-   ##
========================================
+ Coverage     0   63.59%   +63.59%     
========================================
  Files        0      227      +227     
  Lines        0    21753    +21753     
========================================
+ Hits         0    13834    +13834     
- Misses       0     7919     +7919     

Components	Coverage Δ
Analytics	84.09% <72.09%> (∅)
Common	68.79% <85.37%> (∅)
Core	53.31% <38.57%> (∅)
SmartStore	73.65% <ø> (∅)
MobileSync	87.58% <93.26%> (∅)

Files with missing lines	Coverage Δ
...sforceSDKCore/Classes/Views/SFSDKWindowContainer.m	87.50% <100.00%> (ø)
...lesforceSDKCore/Classes/Views/SFSDKWindowManager.m	82.68% <ø> (ø)

... and 209 files with indirect coverage changes