fix(window): reattach overlay after window expand

[yggg]

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Short description of what this resolves:

Fixes #1003

[codecov]

Codecov Report

Merging #1022 into master will decrease coverage by 0.01%.
The diff coverage is 66.66%.

@@            Coverage Diff             @@
##           master    #1022      +/-   ##
==========================================
- Coverage   76.88%   76.86%   -0.02%     
==========================================
  Files         200      200              
  Lines        5975     5983       +8     
  Branches      455      456       +1     
==========================================
+ Hits         4594     4599       +5     
- Misses       1273     1276       +3     
  Partials      108      108

Impacted Files	Coverage Δ
...mework/theme/components/window/window.component.ts	79.31% <100%> (+0.73%)	⬆️
.../theme/components/cdk/overlay/overlay-container.ts	85.71% <50%> (-7.39%)	⬇️