Flaky tests on Chrome/macOS CI job

[mourner]

Looking through CI failures on main commits, it looks like it boils down to two flaky tests on the Chrome/macOS job:

• Map.TouchZoom Layer is rendered correctly while pinch zoom when zoomAnim is false
• GridLayer number of 256px tiles loaded in synchronous animated grid @800x600px Loads 290, unloads 275 tiles on MAD-TRD timeout (>10s)

Would be nice to fix this — flakiness is very detrimental to development process. Aditionally, the second issue is the longest test we have (9–10s) — fixing it will probably involve making it shorter in duration.

[mourner]

cc @plainheart — you added the first test, any ideas on making it more reliable in this environment?

[plainheart]

Hello @mourner, the first test case was done with @Falke-Design's help in #8794. I'm unfamiliar with the test tool, so I'm sorry I can't give some useful ideas on improving the reliability.

[jonkoops]

I am adding this to the 2.0 milestone, as I'd really like to get this sorted before release.