b74d7bfdb4
Now that annotation classes override -isEqual:, it’s no longer appropriate to rely on -isEqual: or -containsObject: to check for the preexistence of an annotation. Those methods become deep equality tests, which have worse performance. Checking for identity allows the developer to add a polyline and polygon with identical coordinates, title, etc. to the map. Implemented a missing -[MGLPolyline isEqual:]. Removed outdated comments about -annotationTagForAnnotation: being expensive.
Darwin
The code in the Darwin platform targets Apple platforms but is not specific to iOS or macOS. This code is not distributed as an SDK in itself, but is required by the Mapbox iOS SDK and Mapbox macOS SDK.
These files depend on the Foundation and Core Foundation frameworks but do not depend on iOS- or macOS–specific frameworks, such as UIKit or AppKit. Any non-cross-platform code is guarded by TargetConditionals.h macros.