New context for local device verification (#12417)

* New context for local device verification

* Fix up tests

* Use PropsWithChildren

src/contexts/LocalDeviceVerificationStateContext.ts

@@ -0,0 +1,27 @@
+/*
+Copyright 2024 The Matrix.org Foundation C.I.C.
+
+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 { createContext } from "react";
+
+/**
+ * React context whose value is whether the local device has been verified.
+ *
+ * (Specifically, this is true if we have done enough verification to confirm that the published public cross-signing
+ * keys are genuine -- which normally means that we or another device will have published a signature of this device.)
+ *
+ * This context is available to all components under {@link LoggedInView}, via {@link MatrixClientContextProvider}.
+ */
+export const LocalDeviceVerificationStateContext = createContext(false);