Switch to the new session API for screen-sharing (#25802)

src/@types/global.d.ts

@@ -32,7 +32,8 @@ type ElectronChannel =
     | "setBadgeCount"
     | "update-downloaded"
     | "userDownloadCompleted"
-    | "userDownloadAction";
+    | "userDownloadAction"
+    | "openDesktopCapturerSourcePicker";
 
 declare global {
     interface Window {

src/vector/platform/ElectronPlatform.tsx

@@ -43,6 +43,7 @@ import { MatrixEvent } from "matrix-js-sdk/src/models/event";
 import { BreadcrumbsStore } from "matrix-react-sdk/src/stores/BreadcrumbsStore";
 import { UPDATE_EVENT } from "matrix-react-sdk/src/stores/AsyncStore";
 import { avatarUrlForRoom, getInitialLetter } from "matrix-react-sdk/src/Avatar";
+import DesktopCapturerSourcePicker from "matrix-react-sdk/src/components/views/elements/DesktopCapturerSourcePicker";
 
 import VectorBasePlatform from "./VectorBasePlatform";
 import { SeshatIndexManager } from "./SeshatIndexManager";
@@ -163,6 +164,14 @@ export default class ElectronPlatform extends VectorBasePlatform {
             });
         });
 
+        window.electron.on("openDesktopCapturerSourcePicker", () => {
+            const { finished } = Modal.createDialog(DesktopCapturerSourcePicker);
+            finished.then(([source]) => {
+                if (!source) return;
+                this.ipc.call("callDisplayMediaCallback", source);
+            });
+        });
+
         this.ipc.call("startSSOFlow", this.ssoID);
 
         BreadcrumbsStore.instance.on(UPDATE_EVENT, this.onBreadcrumbsUpdate);