Make "Snapshot/Screenshot" test page works

[ZihanChen-MSFT]

Please select one of the following

• I am removing an existing difference between facebook/react-native and microsoft/react-native-macos 👍
• I am cherry-picking a change from Facebook's react-native into microsoft/react-native-macos 👍
• I am making a fix / change for the macOS implementation of react-native
• I am making a change required for Microsoft usage of react-native

Summary

• In RNTester, the Snapshot/Screenshot page is originally designed for taking a screenshot from the main window in iOS using NativeModule.
• Before this fix, operations on this test page results in crashing.
• I made it run in macOS with turbo module.
• This change is created based on fb62merge.

Changelog

[macOS] [Fixed] - Make "Snapshot/Screenshot" test page works.

Test Plan

Manually tested.

Microsoft Reviewers: Open in CodeFlow

[alloy]

Welcome to Xcode land 😄

One thing that isn’t immediately clear to me is why this is using Turbo Modules; is it just forward thinking or did you take this module as an entry-point to start your larger work effort on Turbo Modules in RN macOS?

[alloy]

Yep, this seems good to me 👍

The one thing I’m wondering now is if we should wait to merge this into master until we’ve released v0.62 proper (currently still in prerelease), or perhaps you can create a new macos-turbo-modules branch and merge these changes there, an merge all of that work into master later on?

/cc @acoates-ms

[analysis-bot]

Code analysis results:

• eslint found some issues. Run yarn lint --fix to automatically fix problems.