There is now only one instance of mbgl::OfflineFileSource, created when the shared MGLOfflineStorage object is initialized. Also create and use the shared MGLOfflineStorage object when initializing an MGLMapView object. The unified cache file is located in a subdirectory of Application Support, where the SDK has control over the file’s lifetime. The subdirectory is already named after the host application’s bundle identifier, ensuring that each Mapbox-powered application has an independent tile limit. If there’s an ambient cache in a subdirectory of Caches, delete it. If there’s an offline cache in a subdirectory of Documents on iOS or Caches on OS X, move it to the unified cache location in a subdirectory of Application Support.
Fixes the iOS/OS X side of #4338.
Include offline headers in the umbrella header used by the static framework. These includes are already present in the umbrella header used by the dynamic framework. jazzy relies on the static umbrella header to include all the headers, so the offline headers were also missing from documentation.
The tile limit guard (when used) stops a download from continuing
when the tile limit is reached. This wraps the guard in a method
and employs it in both places currently necessary to ensure the
guard has a chance to function. Tests have been updated to
ensure the fix works for a less trivial tile limit scenario.
Although often recommended, CFBundleName is not guaranteed to exist in
an app's configuration. As an identifier of telemetry data, even when
it is present it can be inconsistent because of localization.
CFBundleIdentifier, although possibly longer, will be consistent
across locales and for the lifetime of an app in the App Store even
if the app name changes in any locale.
Due to ARC, MGLOfflinePack can be deallocated at any time following its initialization. -dealloc ensures that the offline region observer is unset, but that step is asynchronous; there is no guarantee that it completes before the first status change update. In fact, the pack is deallocated before the first status change update unless it is captured outside of the MGLOfflinePackAdditionCompletionHandler. The pack nil check is unnecessary because the subsequent code would be a no-op.
Fixed a race condition that could occur if a progress update comes after a call to remove the task but before the removal is complete. Avoid synchronously setting the task’s state inside -resume and -suspend; instead, rely on the observer to set the state asynchronously.
