Use serde_bytes crate

This speeds up serializing and deserializing of binary data.

webrender_api/Cargo.toml

@@ -20,6 +20,7 @@ ipc-channel = {version = "0.10.0", optional = true}
 euclid = { version = "0.17", features = ["serde"] }
 serde = { version = "=1.0.35", features = ["rc"] }
 serde_derive = { version = "=1.0.35", features = ["deserialize_in_place"] }
+serde_bytes = "0.10"
 time = "0.1"
 
 [target.'cfg(target_os = "macos")'.dependencies]

webrender_api/src/api.rs

@@ -2,6 +2,8 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
+extern crate serde_bytes;
+
 use app_units::Au;
 use channel::{self, MsgSender, Payload, PayloadSender, PayloadSenderHelperMethods};
 use std::cell::Cell;
@@ -405,7 +407,11 @@ pub struct UpdateImage {
 
 #[derive(Clone, Deserialize, Serialize)]
 pub enum AddFont {
-    Raw(FontKey, Vec<u8>, u32),
+    Raw(
+        FontKey,
+        #[serde(with = "serde_bytes")] Vec<u8>,
+        u32
+    ),
     Native(FontKey, NativeFontHandle),
 }
 

webrender_api/src/image.rs

@@ -2,6 +2,8 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
+extern crate serde_bytes;
+
 use font::{FontInstanceKey, FontKey, FontTemplate};
 use std::sync::Arc;
 use {DevicePoint, DeviceUintRect, IdNamespace, TileOffset, TileSize};
@@ -110,11 +112,26 @@ impl ImageDescriptor {
 
 #[derive(Clone, Debug, Serialize, Deserialize)]
 pub enum ImageData {
-    Raw(Arc<Vec<u8>>),
-    Blob(BlobImageData),
+    Raw(#[serde(with = "serde_image_data_raw")] Arc<Vec<u8>>),
+    Blob(#[serde(with = "serde_bytes")] BlobImageData),
     External(ExternalImageData),
 }
 
+mod serde_image_data_raw {
+    extern crate serde_bytes;
+
+    use std::sync::Arc;
+    use serde::{Deserializer, Serializer};
+
+    pub fn serialize<'a, S: Serializer>(bytes: &'a Arc<Vec<u8>>, serializer: S) -> Result<S::Ok, S::Error> {
+        serde_bytes::serialize(bytes.as_slice(), serializer)
+    }
+
+    pub fn deserialize<'de, D: Deserializer<'de>>(deserializer: D) -> Result<Arc<Vec<u8>>, D::Error> {
+        serde_bytes::deserialize(deserializer).map(Arc::new)
+    }
+}
+
 impl ImageData {
     pub fn new(bytes: Vec<u8>) -> Self {
         ImageData::Raw(Arc::new(bytes))