Automatically trace CAAnimationDelegate start/stop methods

[armcknight]

Problem Statement

It could be helpful for developers to be made aware of degraded performance of animations they build using Core Animation. We could use our automatic instrumentation to start and stop a span on animationDidStart:/animationDidStop: towards this end.

Solution Brainstorm

We could examine the classes delivered in an application binary and check to see if they conform to the CAAminationDelegate protocol and then swizzle animationDidStart:/animationDidStop: to create the span.

[philipphofmann]

The use case for this is to determine if your animations cause glitches. If we added spans for animations, this wouldn't help much because you don't know which span had glitches. It would make sense to add the amount of total, slow and frozen frames to spans, see #1912

Most animations won't happen for auto-generated UIViewController transactions, but instead for UI event transactions.

Consider repeating animations without an end.

Related to #1843 and getsentry/team-mobile#4

[github-actions]

This issue has gone three weeks without activity. In another week, I will close it.

But! If you comment or otherwise update it, I will reset the clock, and if you label it Status: Backlog or Status: In Progress, I will leave it alone ... forever!

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"A weed is but an unloved flower." ― Ella Wheeler Wilcox 🥀

[github-actions]

This issue has gone three weeks without activity. In another week, I will close it.

But! If you comment or otherwise update it, I will reset the clock, and if you label it Status: Backlog or Status: In Progress, I will leave it alone ... forever!

---

"A weed is but an unloved flower." ― Ella Wheeler Wilcox 🥀