[visionOS] Video fails to render after returning from LinearMediaPlay…

…er fullscreen

https://bugs.webkit.org/show_bug.cgi?id=271024
rdar://123333859

Reviewed by Eric Carlson.

When returning from LinearMediaPlayer fullscreen we failed to clear the video receiver endpoint from
MediaPlayer, leaving it in a state where it was rendering to an endpoint that no longer existed. We
attempted to clear the endpoint in PlaybackSessionInterfaceLMK's implementation of
-linearMediaPlayer:didExitFullscreenWithError:, but it turns out this delegate method isn't called
when using `allowFullScreenFromInline`. Instead, clear the entpoint in -linearMediaPlayerToggleInlineMode:.

With this bug fixed, there is a second issue where the inline controls do not appear. This ended up
being a side effect of setting VideoPresentationInterface's captionsLayer on the LinearMediaPlayer.
Since there is still outstanding work for supporting captions (see rdar://124223292), for now just
pass an empty layer to LinearMediaPlayer.

* Source/WebKit/Platform/ios/PlaybackSessionInterfaceLMK.mm:
(-[WKLinearMediaPlayerDelegate linearMediaPlayerToggleInlineMode:]):
(-[WKLinearMediaPlayerDelegate linearMediaPlayer:didExitFullscreenWithError:]): Deleted.
* Source/WebKit/Platform/ios/VideoPresentationInterfaceLMK.mm:
(WebKit::VideoPresentationInterfaceLMK::setupPlayerViewController):

Canonical link: https://commits.webkit.org/276179@main

Source/WebKit/Platform/ios/PlaybackSessionInterfaceLMK.mm

@@ -182,14 +182,12 @@ - (void)linearMediaPlayer:(WKSLinearMediaPlayer *)player setLegibleTrack:(WKSLin
 
 - (void)linearMediaPlayerToggleInlineMode:(WKSLinearMediaPlayer *)player
 {
-    if (auto model = _model.get())
-        model->toggleFullscreen();
-}
+    auto model = _model.get();
+    if (!model)
+        return;
 
-- (void)linearMediaPlayer:(WKSLinearMediaPlayer *)player didExitFullscreenWithError:(NSError * _Nullable)error
-{
-    if (auto model = _model.get())
-        model->setVideoReceiverEndpoint(nullptr);
+    model->toggleFullscreen();
+    model->setVideoReceiverEndpoint(nullptr);
 }
 
 - (void)linearMediaPlayer:(WKSLinearMediaPlayer *)player setVideoReceiverEndpoint:(xpc_object_t)videoReceiverEndpoint

Source/WebKit/Platform/ios/VideoPresentationInterfaceLMK.mm

@@ -70,8 +70,8 @@
     linearMediaPlayer().allowFullScreenFromInline = YES;
     linearMediaPlayer().contentType = WKSLinearMediaContentTypePlanar;
     linearMediaPlayer().presentationMode = WKSLinearMediaPresentationModeInline;
-    linearMediaPlayer().captionLayer = captionsLayer();
-    linearMediaPlayer().videoLayer = [m_playerLayerView playerLayer];
+    // FIXME: pass a valid caption layer (rdar://124223292)
+    linearMediaPlayer().captionLayer = CALayer.layer;
 
     m_playerViewController = [linearMediaPlayer() makeViewController];
 }