This uses the pause/resume API on the default file source to pause network and revalidation activity when the host iOS application goes into the background. Activity is resumed when the host application goes into the foreground. The intention of this change is to avoid edge cases on some OSs where resources (i.e. sqlite) are not available when the host app is not visible to the user.
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.