Repository: servo/servo
File: components/constellation/constellation.rs (Rust)

Code before:
        }
        self.handle_shutdown();

        if !opts::get().multiprocess {
            StyleThreadPool::shutdown();
        }

        // Shut down the fetch thread started above.
        exit_fetch_thread();
        join_handle
            .join()
            .expect("Failed to join on the fetch thread in the constellation");

        // Note: the last thing the constellation does, is asking the embedder to
        // shut down. This helps ensure we've shut down all our internal threads before
        // de-initializing Servo (see the `thread_count` warning on MacOS).
        debug!("Asking embedding layer to complete shutdown.");
        self.embedder_proxy.send(EmbedderMsg::ShutdownComplete);
    }

    /// Helper that sends a message to the event loop of a given pipeline.
    /// Returns `false` after printing a warning if the pipeline does not exist.
    fn send_handling_error(
        &mut self,
        pipeline_id: PipelineId,
        msg: ScriptThreadMessage,
        warn_msg: &str,
    ) -> bool {
        let result = match self.pipelines.get(&pipeline_id) {
            Some(pipeline) => pipeline.event_loop.send(msg),
            None => {
                warn!("{}: {}", pipeline_id, warn_msg);
                return false;
            },
        };
        if let Err(err) = result {
            self.handle_send_error(pipeline_id, err);
        }
        true
    }

    /// Generate a new pipeline id namespace.
    fn next_pipeline_namespace_id(&mut self) -> PipelineNamespaceId {
        let namespace_id = self.next_pipeline_namespace_id;
        let PipelineNamespaceId(ref mut i) = self.next_pipeline_namespace_id;
        *i += 1;
        namespace_id
    }

    fn next_browsing_context_group_id(&mut self) -> BrowsingContextGroupId {
        let id = self.browsing_context_group_next_id;

Review comment (suggestion):
```suggestion
        message: ScriptThreadMessage,
```

Code after:
        }
        self.handle_shutdown();

        if !opts::get().multiprocess {
            StyleThreadPool::shutdown();
        }

        // Shut down the fetch thread started above.
        exit_fetch_thread();
        join_handle
            .join()
            .expect("Failed to join on the fetch thread in the constellation");

        // Note: the last thing the constellation does, is asking the embedder to
        // shut down. This helps ensure we've shut down all our internal threads before
        // de-initializing Servo (see the `thread_count` warning on MacOS).
        debug!("Asking embedding layer to complete shutdown.");
        self.embedder_proxy.send(EmbedderMsg::ShutdownComplete);
    }

    /// Helper that sends a message to the event loop of a given pipeline, logging the
    /// given failure message and returning `false` on failure.
    fn send_message_to_pipeline(
        &mut self,
        pipeline_id: PipelineId,
        message: ScriptThreadMessage,
        failure_message: &str,
    ) -> bool {
        let result = match self.pipelines.get(&pipeline_id) {
            Some(pipeline) => pipeline.event_loop.send(message),
            None => {
                warn!("{pipeline_id}: {failure_message}");
                return false;
            },
        };
        if let Err(err) = result {
            self.handle_send_error(pipeline_id, err);
        }
        true
    }

    /// Generate a new pipeline id namespace.
    fn next_pipeline_namespace_id(&mut self) -> PipelineNamespaceId {
        let namespace_id = self.next_pipeline_namespace_id;
        let PipelineNamespaceId(ref mut i) = self.next_pipeline_namespace_id;
        *i += 1;
        namespace_id
    }

    fn next_browsing_context_group_id(&mut self) -> BrowsingContextGroupId {
        let id = self.browsing_context_group_next_id;