2.x: cancel upstream first, dispose worker last

[akarnokd]

This PR makes sure the Scheduler.Worker is disposed only after

• disposing/cancelling the upstream,
• emitting terminal events.

This may help with situations when the worker-dispose interrupts a thread that is blocked and the InterruptedException handler checks for the stream to be disposed so the exception can be safely ignored (and thus not end up in the RxJavaPlugins.onError handler to crash the app).

Related: #4863

[codecov]

Codecov Report

Merging #5075 into 2.x will increase coverage by -0.11%.

@@             Coverage Diff              @@
##                2.x    #5075      +/-   ##
============================================
- Coverage     95.65%   95.55%   -0.11%     
+ Complexity     5544     5542       -2     
============================================
  Files           612      612              
  Lines         39575    39561      -14     
  Branches       5554     5553       -1     
============================================
- Hits          37857    37803      -54     
- Misses          746      771      +25     
- Partials        972      987      +15

Impacted Files	Coverage Δ	Complexity Δ
...ternal/operators/flowable/FlowableBufferTimed.java	91% <100%> (+0.35%)	5 <ø> (ø)	❌
...operators/flowable/FlowableThrottleFirstTimed.java	96.49% <100%> (-0.12%)	2 <ø> (ø)
...al/operators/observable/ObservableBufferTimed.java	91.72% <100%> (ø)	5 <ø> (ø)	❌
...rnal/operators/flowable/FlowableDebounceTimed.java	93.82% <100%> (-0.08%)	2 <ø> (ø)
.../operators/observable/ObservableDebounceTimed.java	94.28% <100%> (-0.16%)	2 <ø> (ø)
...vex/internal/operators/flowable/FlowableDelay.java	100% <100%> (ø)	3 <ø> (ø)	❌
...internal/operators/observable/ObservableDelay.java	100% <100%> (ø)	3 <ø> (ø)	❌
...ernal/operators/flowable/FlowableTimeoutTimed.java	91.66% <100%> (-0.27%)	4 <ø> (ø)
...l/operators/observable/ObservableTimeoutTimed.java	93.1% <100%> (-0.23%)	4 <ø> (ø)
...ators/observable/ObservableThrottleFirstTimed.java	95.23% <100%> (-0.22%)	2 <ø> (ø)
... and 50 more

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 14ea26b...d0ffd35. Read the comment docs.