Adding engine unit testing for iOS. #31288
Description
We currently only have a few engine unit tests in ObjC that test some channels implementation. That works because the channels implementation can be run on the Mac with a GTest harness.
There are currently 2 ways that we can do this:
1. Create a different GTest harness for iOS.
Pros:
We have already been using GTest in the Engine code extensively, adding another GTest harness is relatively easier to maintain.
Cons:
GTest for iOS might not be too straightforward for people who are familiar with writing iOS test in XCTest.
2. Using XCTest for iOS
Pros:
Standard way to test iOS. Easier to people who are familiar with standard iOS development.
Better Xcode integration.
Cons:
Adding another dependency to the Engine, can be a litter harder to maintain.