libservo: change 'request_fullscreen_state_change' API to a notification (#35445)

Signed-off-by: Mukilan Thiyagarajan <mukilan@igalia.com>

components/constellation/tracing.rs

@@ -220,7 +220,9 @@ mod from_script {
                 Self::SetCursor(..) => target_variant!("SetCursor"),
                 Self::NewFavicon(..) => target_variant!("NewFavicon"),
                 Self::HistoryChanged(..) => target_variant!("HistoryChanged"),
-                Self::SetFullscreenState(..) => target_variant!("SetFullscreenState"),
+                Self::NotifyFullscreenStateChanged(..) => {
+                    target_variant!("NotifyFullscreenStateChanged")
+                },
                 Self::NotifyLoadStatusChanged(_, LoadStatus::Started) => {
                     target_variant!("NotifyLoadStatusChanged(LoadStatus::Started)")
                 },

components/script/dom/document.rs

@@ -4250,7 +4250,7 @@ impl Document {
         let window = self.window();
         // Step 6
         if !error {
-            let event = EmbedderMsg::SetFullscreenState(self.webview_id(), true);
+            let event = EmbedderMsg::NotifyFullscreenStateChanged(self.webview_id(), true);
             self.send_to_embedder(event);
         }
 
@@ -4292,7 +4292,7 @@ impl Document {
 
         let window = self.window();
         // Step 8
-        let event = EmbedderMsg::SetFullscreenState(self.webview_id(), false);
+        let event = EmbedderMsg::NotifyFullscreenStateChanged(self.webview_id(), false);
         self.send_to_embedder(event);
 
         // Step 9

components/servo/lib.rs

@@ -871,11 +871,11 @@ impl Servo {
                     webview.set_url(current_url);
                 }
             },
-            EmbedderMsg::SetFullscreenState(webview_id, fullscreen) => {
+            EmbedderMsg::NotifyFullscreenStateChanged(webview_id, fullscreen) => {
                 if let Some(webview) = self.get_webview_handle(webview_id) {
                     webview
                         .delegate()
-                        .request_fullscreen_state_change(webview, fullscreen);
+                        .notify_fullscreen_state_changed(webview, fullscreen);
                 }
             },
             EmbedderMsg::WebResourceRequested(

components/servo/webview_delegate.rs

@@ -188,6 +188,12 @@ pub trait WebViewDelegate {
     /// Notifies the embedder about media session events
     /// (i.e. when there is metadata for the active media session, playback state changes...).
     fn notify_media_session_event(&self, _webview: WebView, _event: MediaSessionEvent) {}
+    /// A notification that the [`WebView`] has entered or exited fullscreen mode. This is an
+    /// opportunity for the embedder to transition the containing window into or out of fullscreen
+    /// mode and to show or hide extra UI elements. Regardless of how the notification is handled,
+    /// the page will enter or leave fullscreen state internally according to the [Fullscreen
+    /// API](https://fullscreen.spec.whatwg.org/).
+    fn notify_fullscreen_state_changed(&self, _webview: WebView, _: bool) {}
 
     /// Whether or not to allow a [`WebView`] to load a URL in its main frame or one of its
     /// nested `<iframe>`s. [`NavigationRequest`]s are accepted by default.
@@ -239,9 +245,6 @@ pub trait WebViewDelegate {
         let _ = result_sender.send(ContextMenuResult::Ignored);
     }
 
-    /// Enter or exit fullscreen
-    fn request_fullscreen_state_change(&self, _webview: WebView, _: bool) {}
-
     /// Open dialog to select bluetooth device.
     /// TODO: This API needs to be reworked to match the new model of how responses are sent.
     fn show_bluetooth_device_dialog(

components/shared/embedder/lib.rs

@@ -209,8 +209,8 @@ pub enum EmbedderMsg {
     NewFavicon(WebViewId, ServoUrl),
     /// The history state has changed.
     HistoryChanged(WebViewId, Vec<ServoUrl>, usize),
-    /// Enter or exit fullscreen
+    /// Entered or exited fullscreen.
-    SetFullscreenState(WebViewId, bool),
+    NotifyFullscreenStateChanged(WebViewId, bool),
     /// The [`LoadStatus`] of the Given `WebView` has changed.
     NotifyLoadStatusChanged(WebViewId, LoadStatus),
     WebResourceRequested(
@@ -277,7 +277,9 @@ impl Debug for EmbedderMsg {
             EmbedderMsg::SetCursor(..) => write!(f, "SetCursor"),
             EmbedderMsg::NewFavicon(..) => write!(f, "NewFavicon"),
             EmbedderMsg::HistoryChanged(..) => write!(f, "HistoryChanged"),
-            EmbedderMsg::SetFullscreenState(..) => write!(f, "SetFullscreenState"),
+            EmbedderMsg::NotifyFullscreenStateChanged(..) => {
+                write!(f, "NotifyFullscreenStateChanged")
+            },
             EmbedderMsg::NotifyLoadStatusChanged(_, status) => {
                 write!(f, "NotifyLoadStatusChanged({status:?})")
             },

ports/servoshell/desktop/app_state.rs

@@ -473,7 +473,7 @@ impl WebViewDelegate for RunningAppState {
         self.inner_mut().need_update = true;
     }
 
-    fn request_fullscreen_state_change(&self, _webview: servo::WebView, fullscreen_state: bool) {
+    fn notify_fullscreen_state_changed(&self, _webview: servo::WebView, fullscreen_state: bool) {
         self.inner().window.set_fullscreen(fullscreen_state);
     }