compositor: Hide IpcSender as implementation detail (#38963)

The `CrossProcessCompositorApi` already provides methods for most
messages.
Remove the `sender()` method, and hide the IpcSender as an
implementation detail. This is a preparation for abstracting over the
internal IpcSender.

Testing: No functional changes

---------

Signed-off-by: Jonathan Schwender <schwenderjonathan@gmail.com>

components/script/dom/htmlmetaelement.rs

@@ -4,7 +4,6 @@
 
 use std::str::FromStr;
 
-use compositing_traits::CompositorMsg;
 use compositing_traits::viewport_description::ViewportDescription;
 use dom_struct::dom_struct;
 use html5ever::{LocalName, Prefix, local_name, ns};
@@ -136,12 +135,7 @@ impl HTMLMetaElement {
         if let Ok(viewport) = ViewportDescription::from_str(&content.value()) {
             self.owner_window()
                 .compositor_api()
-                .sender()
+                .viewport(self.owner_window().webview_id(), viewport);
-                .send(CompositorMsg::Viewport(
-                    self.owner_window().webview_id(),
-                    viewport,
-                ))
-                .unwrap();
         }
     }
 

components/script/script_thread.rs

@@ -36,7 +36,7 @@ use base::cross_process_instant::CrossProcessInstant;
 use base::id::{BrowsingContextId, HistoryStateId, PipelineId, PipelineNamespace, WebViewId};
 use canvas_traits::webgl::WebGLPipeline;
 use chrono::{DateTime, Local};
-use compositing_traits::{CompositorMsg, CrossProcessCompositorApi, PipelineExitSource};
+use compositing_traits::{CrossProcessCompositorApi, PipelineExitSource};
 use constellation_traits::{
     JsEvalResult, LoadData, LoadOrigin, NavigationHistoryBehavior, ScriptToConstellationChan,
     ScriptToConstellationMessage, StructuredSerializedData, WindowSizeType,
@@ -2956,13 +2956,7 @@ impl ScriptThread {
             .ok();
 
         self.compositor_api
-            .sender()
+            .pipeline_exited(webview_id, id, PipelineExitSource::Script);
-            .send(CompositorMsg::PipelineExited(
-                webview_id,
-                id,
-                PipelineExitSource::Script,
-            ))
-            .ok();
 
         debug!("{id}: Finished pipeline exit");
     }

components/servo/lib.rs

@@ -1101,7 +1101,7 @@ fn create_compositor_channel(
     let (compositor_ipc_sender, compositor_ipc_receiver) =
         ipc::channel().expect("ipc channel failure");
 
-    let cross_process_compositor_api = CrossProcessCompositorApi(compositor_ipc_sender);
+    let cross_process_compositor_api = CrossProcessCompositorApi::new(compositor_ipc_sender);
     let compositor_proxy = CompositorProxy {
         sender,
         cross_process_compositor_api,

components/shared/compositing/lib.rs

@@ -174,9 +174,14 @@ pub struct CompositionPipeline {
 
 /// A mechanism to send messages from ScriptThread to the parent process' WebRender instance.
 #[derive(Clone, Deserialize, MallocSizeOf, Serialize)]
-pub struct CrossProcessCompositorApi(pub IpcSender<CompositorMsg>);
+pub struct CrossProcessCompositorApi(IpcSender<CompositorMsg>);
 
 impl CrossProcessCompositorApi {
+    /// Create a new [`CrossProcessCompositorApi`] struct.
+    pub fn new(sender: IpcSender<CompositorMsg>) -> Self {
+        CrossProcessCompositorApi(sender)
+    }
+
     /// Create a new [`CrossProcessCompositorApi`] struct that does not have a listener on the other
     /// end to use for unit testing.
     pub fn dummy() -> Self {
@@ -184,11 +189,6 @@ impl CrossProcessCompositorApi {
         Self(sender)
     }
 
-    /// Get the sender for this proxy.
-    pub fn sender(&self) -> &IpcSender<CompositorMsg> {
-        &self.0
-    }
-
     /// Inform WebRender of the existence of this pipeline.
     pub fn send_initial_transaction(&self, pipeline: WebRenderPipelineId) {
         if let Err(e) = self.0.send(CompositorMsg::SendInitialTransaction(pipeline)) {
@@ -352,6 +352,25 @@ impl CrossProcessCompositorApi {
         ));
         receiver.recv().unwrap()
     }
+
+    pub fn viewport(&self, webview_id: WebViewId, description: ViewportDescription) {
+        let _ = self
+            .0
+            .send(CompositorMsg::Viewport(webview_id, description));
+    }
+
+    pub fn pipeline_exited(
+        &self,
+        webview_id: WebViewId,
+        pipeline_id: PipelineId,
+        source: PipelineExitSource,
+    ) {
+        let _ = self.0.send(CompositorMsg::PipelineExited(
+            webview_id,
+            pipeline_id,
+            source,
+        ));
+    }
 }
 
 /// This trait is used as a bridge between the different GL clients