Stable release branch hotfix: Fix camera turning back on when turned off on connecting screen (#2458)

Author: JamesBurnside

packages/calling-component-bindings/src/handlers/createHandlers.ts

@@ -133,6 +133,31 @@ export const createDefaultCallingHandlers = memoizeOne(
     };
 
     const onToggleCamera = async (options?: VideoStreamOptions): Promise<void> => {
+      const previewOn = _isPreviewOn(callClient.getState().deviceManager);
+
+      if (previewOn && call && call.state === 'Connecting') {
+        // This is to workaround: https://skype.visualstudio.com/SPOOL/_workitems/edit/3030558.
+        // The root cause of the issue is caused by never transitioning the unparented view to the
+        // call object when going from configuration page (disconnected call state) to connecting.
+        //
+        // Currently the only time the local video stream is moved from unparented view to the call
+        // object is when we transition from connecting -> call state. If the camera was on,
+        // inside the MediaGallery we trigger toggleCamera. This triggers onStartLocalVideo which
+        // destroys the unparentedView and creates a new stream in the call - so all looks well.
+        //
+        // However, if someone turns off their camera during the lobbyOrConnecting screen, the
+        // call.localVideoStreams will be empty (as the stream is currently stored in the unparented
+        // views and was never transitioned to the call object) and thus we incorrectly try to create
+        // a new video stream for the call object, instead of only stopping the unparented view.
+        //
+        // The correct fix for this is to ensure that callAgent.onStartCall is called with the
+        // localvideostream as a videoOption. That will mean call.onLocalVideoStreamsUpdated will
+        // be triggered when the call is in connecting state, which we can then transition the
+        // local video stream to the stateful call client and get into a clean state.
+        await onDisposeLocalStreamView();
+        return;
+      }
+
       if (call && (_isInCall(call.state) || _isInLobbyOrConnecting(call.state))) {
         const stream = call.localVideoStreams.find((stream) => stream.mediaStreamType === 'Video');
         if (stream) {
@@ -143,7 +168,6 @@ export const createDefaultCallingHandlers = memoizeOne(
       } else {
         const selectedCamera = callClient.getState().deviceManager.selectedCamera;
         if (selectedCamera) {
-          const previewOn = _isPreviewOn(callClient.getState().deviceManager);
           if (previewOn) {
             await onDisposeLocalStreamView();
           } else {