Delegate Drawable copy to background thread

[xgouchet]

What does this PR do?

Our previous mechanism of copying a drawable's content was performed on the main thread. When starting an app, this would create a lot of main thread task to run. And any new image would also take some of the main thread time, creating a lot of jank frames in any non hello world app.

This will fix the performance issue some of our customers started to notice when enabling SR.

[codecov-commenter]

Codecov Report

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

Project coverage is 83.02%. Comparing base (daec9a0) to head (efb6200).

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #2048      +/-   ##
===========================================
- Coverage    83.10%   83.02%   -0.09%     
===========================================
  Files          494      494              
  Lines        17720    17688      -32     
  Branches      2686     2684       -2     
===========================================
- Hits         14726    14684      -42     
- Misses        2253     2259       +6     
- Partials       741      745       +4     

Files	Coverage Δ
...nreplay/internal/recorder/SessionReplayRecorder.kt	96.61% <100.00%> (+0.09%)	:arrow_up:
...ssionreplay/internal/recorder/TreeViewTraversal.kt	95.92% <100.00%> (+0.80%)	:arrow_up:
...roid/sessionreplay/internal/utils/DrawableUtils.kt	93.65% <100.00%> (ø)

... and 30 files with indirect coverage changes