vector-im/element-x-ios/issues/31 - Implement simple SaS sesson verification

* vector-im/element-x-ios/issues/31 - Session verification unit and UI tests
* Fix ImageAnonymizer tests when running on Apple Silicon
* Rename SessionVerification to SessionVerificationScreen

ElementX/Sources/Screens/SessionVerification/SessionVerificationModels.swift

@@ -0,0 +1,46 @@
+// 
+// Copyright 2021 New Vector Ltd
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+import Foundation
+
+// MARK: View model
+
+enum SessionVerificationViewModelAction {
+    case finished
+}
+
+// MARK: View
+
+struct SessionVerificationViewState: BindableState {
+    var verificationState: SessionVerificationStateMachine.State = .initial
+    
+    var shouldDisableDismissButton: Bool {
+        verificationState != .verified
+    }
+    
+    var shouldDisableCancelButton: Bool {
+        verificationState == .verified
+    }
+}
+
+enum SessionVerificationViewAction {
+    case start
+    case restart
+    case accept
+    case decline
+    case dismiss
+    case cancel
+}