rAF logic was introduced almost three years ago relative to this commit,
as a primary method for scheduling animation (see gh-1578 pull).

With it there was two substantial changes - one was explicitly mentioned
and the other was not.

First, if browser window was hidden aka document.hidden === true
it would immediately execute all scheduled animation without waiting
for time pass i.e. tick time become 0 instead of 13 ms of a default value.

Which created possibility for circular executions in case if complete
method executed the same animation (see gh-3434 issue).

And the second one - since then there was two ways of scheduling animation:
with setInterval and requestAnimationFrame, but there was a
difference in their execution.

In case of setInterval it waited default jQuery.fx.interval value before
actually starting the new tick, not counting the first step which wasn't
set to be executed through tick method (aka jQuery.fx.tick).

Whereas requestAnimationFrame first scheduled the call and executed
the step method right after that, counting the first call of
jQuery.fx.timer, tick was happening twice in one frame.

But since tests explicitly disabled rAF method i.e.
requestAnimationFrame = null and checking only setInterval logic,
since it's impossible to do it otherwise - we missed that change.

Faulty logic also was presented with cancelAnimationFrame, which couldn't
clear any timers since raf scheduler didn't define new timerId value.

Because that change was so subtle, apparently no user noticed it proving
that both cancelAnimationFrame and clearInterval code paths are redundant.

Since cancelAnimationFrame didn't work properly and rAF is and was a primary
used code path, plus the same approach is used in other popular animation libs.

Therefore those code paths were removed.

These changes also replace two different functions which schedule the animation
with one, which checks what type of logic should be used and executes it
appropriatley, but for secondary path it now uses setTimeout making it more
consistent with rAF path.

Since ticks are happening globally we also don't require to listen
visibilitychange event.

It also changes the way how first call is scheduled so execution of
animation will not happen twice in one frame.

No new tests were not introduced, since now setTimeout logic should be
equivalent to the rAF one, but one test was changed since now we actually
execute animation at the first tick.

Fixes gh-3434

Summary

Checklist

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• All authors have signed the CLA at https://contribute.jquery.com/CLA/
• New tests have been added to show the fix or feature works
• Grunt build and unit tests pass locally with these changes
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