Add background app refresh support (#892)

* Add background app refresh support

* Cleanup: move methods around so delegates are implemented above privates and privates are ordered better

* Add discardableResult on the userSessionStore's refreshRestorationToken

ElementX/SupportingFiles/Info.plist

@@ -2,6 +2,10 @@
 <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
 <plist version="1.0">
 <dict>
+	<key>BGTaskSchedulerPermittedIdentifiers</key>
+	<array>
+		<string>io.element.elementx.background.refresh</string>
+	</array>
 	<key>CFBundleDevelopmentRegion</key>
 	<string>$(DEVELOPMENT_LANGUAGE)</string>
 	<key>CFBundleDisplayName</key>
@@ -30,6 +34,10 @@
 	<array>
 		<string>INSendMessageIntent</string>
 	</array>
+	<key>UIBackgroundModes</key>
+	<array>
+		<string>fetch</string>
+	</array>
 	<key>UILaunchStoryboardName</key>
 	<string>LaunchScreen</string>
 	<key>UISupportedInterfaceOrientations</key>

ElementX/SupportingFiles/target.yml

@@ -64,6 +64,12 @@ targets:
         ]
         NSCameraUsageDescription: The camera is used to take and upload photos and videos.
         NSMicrophoneUsageDescription: The microphone is used to take videos.
+        UIBackgroundModes: [
+          fetch
+        ]
+        BGTaskSchedulerPermittedIdentifiers: [
+          io.element.elementx.background.refresh
+        ]
 
 
     settings: