Hide screenshare button in video rooms on Desktop (#9045)

* Hide screenshare button in video rooms on Desktop

* Fix tests

Author: robintown

src/BasePlatform.ts

@@ -288,6 +288,10 @@ export default abstract class BasePlatform {
         return false;
     }
 
+    public supportsJitsiScreensharing(): boolean {
+        return true;
+    }
+
     public overrideBrowserShortcuts(): boolean {
         return false;
     }

src/utils/WidgetUtils.ts

@@ -26,6 +26,7 @@ import { CallType } from "matrix-js-sdk/src/webrtc/call";
 import { randomString, randomLowercaseString, randomUppercaseString } from "matrix-js-sdk/src/randomstring";
 
 import { MatrixClientPeg } from '../MatrixClientPeg';
+import PlatformPeg from '../PlatformPeg';
 import SdkConfig from "../SdkConfig";
 import dis from '../dispatcher/dispatcher';
 import WidgetEchoStore from '../stores/WidgetEchoStore';
@@ -510,6 +511,7 @@ export default class WidgetUtils {
             'roomId=$matrix_room_id',
             'theme=$theme',
             'roomName=$roomName',
+            `supportsScreensharing=${PlatformPeg.get().supportsJitsiScreensharing()}`,
         ];
         if (opts.auth) {
             queryStringParts.push(`auth=${opts.auth}`);

test/createRoom-test.ts

@@ -19,20 +19,24 @@ import { MatrixClient } from "matrix-js-sdk/src/matrix";
 import { IDevice } from "matrix-js-sdk/src/crypto/deviceinfo";
 import { RoomType } from "matrix-js-sdk/src/@types/event";
 
-import { stubClient, setupAsyncStoreWithClient } from "./test-utils";
+import { stubClient, setupAsyncStoreWithClient, mockPlatformPeg } from "./test-utils";
 import { MatrixClientPeg } from "../src/MatrixClientPeg";
 import WidgetStore from "../src/stores/WidgetStore";
 import WidgetUtils from "../src/utils/WidgetUtils";
 import { VIDEO_CHANNEL_MEMBER } from "../src/utils/VideoChannelUtils";
 import createRoom, { canEncryptToAllUsers } from '../src/createRoom';
 
 describe("createRoom", () => {
+    mockPlatformPeg();
+
     let client: MatrixClient;
     beforeEach(() => {
         stubClient();
         client = MatrixClientPeg.get();
     });
 
+    afterEach(() => jest.clearAllMocks());
+
     it("sets up video rooms correctly", async () => {
         setupAsyncStoreWithClient(WidgetStore.instance, client);
         jest.spyOn(WidgetUtils, "waitForRoomWidget").mockResolvedValue();