Add support for reading accounts from Element Classic.

ElementX/Sources/Other/InfoPlistReader.swift

@@ -23,6 +23,10 @@ struct InfoPlistReader {
         static let bundleURLTypes = "CFBundleURLTypes"
         static let bundleURLName = "CFBundleURLName"
         static let bundleURLSchemes = "CFBundleURLSchemes"
+        
+        static let classicAppGroupIdentifier = "classicAppGroupIdentifier"
+        static let classicAppKeychainServiceIdentifier = "classicAppKeychainServiceIdentifier"
+        static let classicAppKeychainAccessGroupIdentifier = "classicAppKeychainAccessGroupIdentifier"
     }
     
     private enum Values {
@@ -115,8 +119,23 @@ struct InfoPlistReader {
         return utType.lowercased()
     }
     
+    // MARK: - Sign in with Classic app
+    
+    var classicAppGroupIdentifier: String? {
+        infoPlistValue(forKey: Keys.classicAppGroupIdentifier)
+    }
+    
+    var classicAppKeychainServiceIdentifier: String? {
+        infoPlistValue(forKey: Keys.classicAppKeychainServiceIdentifier)
+    }
+    
+    var classicAppKeychainAccessGroupIdentifier: String? {
+        infoPlistValue(forKey: Keys.classicAppKeychainAccessGroupIdentifier)
+    }
+    
     // MARK: - Private
     
+    @_disfavoredOverload // Make sure optional types default to the optional version below.
     private func infoPlistValue<T>(forKey key: String) -> T {
         guard let result = bundle.object(forInfoDictionaryKey: key) as? T else {
             fatalError("Add \(key) into your target's Info.plst")
@@ -124,6 +143,10 @@ struct InfoPlistReader {
         return result
     }
     
+    private func infoPlistValue<T>(forKey key: String) -> T? {
+        bundle.object(forInfoDictionaryKey: key) as? T
+    }
+    
     private func customSchemeForName(_ name: String) -> String {
         let urlTypes: [[String: Any]] = infoPlistValue(forKey: Keys.bundleURLTypes)