Use non-IPC webrender API over explicit IPC channels.

components/net_traits/Cargo.toml

@@ -37,7 +37,7 @@ servo_url = {path = "../url"}
 time = "0.1"
 url = "2.0"
 uuid = {version = "0.8", features = ["v4", "serde"]}
-webrender_api = {git = "https://github.com/servo/webrender", features = ["ipc"]}
+webrender_api = {git = "https://github.com/servo/webrender"}
 
 [dev-dependencies]
 std_test_override = { path = "../std_test_override" }

components/net_traits/image_cache.rs

@@ -5,6 +5,7 @@
 use crate::image::base::{Image, ImageMetadata};
 use crate::request::CorsSettings;
 use crate::FetchResponseMsg;
+use crate::WebrenderIpcSender;
 use ipc_channel::ipc::IpcSender;
 use servo_url::{ImmutableOrigin, ServoUrl};
 use std::sync::Arc;
@@ -101,7 +102,7 @@ pub enum UsePlaceholder {
 // ======================================================================
 
 pub trait ImageCache: Sync + Send {
-    fn new(webrender_api: webrender_api::RenderApi) -> Self
+    fn new(webrender_api: WebrenderIpcSender) -> Self
     where
         Self: Sized;
 

components/net_traits/lib.rs

@@ -33,6 +33,7 @@ use msg::constellation_msg::HistoryStateId;
 use servo_url::ServoUrl;
 use std::error::Error;
 use time::precise_time_ns;
+use webrender_api::ImageKey;
 
 pub mod blob_url_store;
 pub mod filemanager_thread;
@@ -755,3 +756,32 @@ pub fn http_percent_encode(bytes: &[u8]) -> String {
 
     percent_encoding::percent_encode(bytes, HTTP_VALUE).to_string()
 }
+
+#[derive(Deserialize, Serialize)]
+pub enum WebrenderImageMsg {
+    UpdateResources(Vec<webrender_api::ResourceUpdate>),
+    GenerateImageKey(IpcSender<ImageKey>),
+}
+
+#[derive(Clone, Deserialize, Serialize)]
+pub struct WebrenderIpcSender(IpcSender<WebrenderImageMsg>);
+
+impl WebrenderIpcSender {
+    pub fn new(sender: IpcSender<WebrenderImageMsg>) -> Self {
+        Self(sender)
+    }
+
+    pub fn generate_image_key(&self) -> ImageKey {
+        let (sender, receiver) = ipc::channel().unwrap();
+        self.0
+            .send(WebrenderImageMsg::GenerateImageKey(sender))
+            .expect("error sending image key generation");
+        receiver.recv().expect("error receiving image key result")
+    }
+
+    pub fn update_resources(&self, updates: Vec<webrender_api::ResourceUpdate>) {
+        if let Err(e) = self.0.send(WebrenderImageMsg::UpdateResources(updates)) {
+            warn!("Error sending image update: {}", e);
+        }
+    }
+}