refactor ShareType

Author: theScrabi

owncloudComLibrary/src/main/java/com/owncloud/android/lib/resources/shares/RemoteShare.kt

@@ -106,17 +106,7 @@ enum class ShareType constructor(val value: Int) {
     FEDERATED(6);
 
     companion object {
-        fun fromValue(value: Int): ShareType? {
-            return when (value) {
-                -1 -> UNKNOWN
-                0 -> USER
-                1 -> GROUP
-                3 -> PUBLIC_LINK
-                4 -> EMAIL
-                5 -> CONTACT
-                6 -> FEDERATED
-                else -> null
-            }
-        }
+        private val values = values();
+        fun fromValue(value: Int) = values.firstOrNull { it.value == value }
     }
 }