Support package-prefs.json for libsimpleservo

Cargo.lock

@@ -5408,6 +5408,7 @@ dependencies = [
  "libloading 0.5.2",
  "libservo",
  "log",
+ "serde_json",
  "servo-media",
  "surfman",
  "webxr",

ports/libsimpleservo/api/Cargo.toml

@@ -30,6 +30,7 @@ libloading = "0.5"
 
 [build-dependencies]
 gl_generator = "0.14"
+serde_json = "1.0"
 
 [features]
 debugmozjs = ["libservo/debugmozjs"]

ports/libsimpleservo/api/build.rs

@@ -3,6 +3,7 @@
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
 use gl_generator::{Api, Fallbacks, Profile, Registry};
+use serde_json::{self, Value};
 use std::env;
 use std::fs::File;
 use std::path::PathBuf;
@@ -40,4 +41,30 @@ fn main() {
             .write_bindings(gl_generator::StructGenerator, &mut file)
             .unwrap();
     }
+
+    // Merge prefs.json and package-prefs.json
+    let mut default_prefs = PathBuf::from(env!("CARGO_MANIFEST_DIR"));
+    default_prefs.push("../../../resources/prefs.json");
+    let mut prefs: Value = serde_json::from_reader(File::open(&default_prefs).unwrap()).unwrap();
+    let mut pkg_prefs = PathBuf::from(env!("CARGO_MANIFEST_DIR"));
+    pkg_prefs.push("../../../resources/package-prefs.json");
+    let pkg_prefs: Value = serde_json::from_reader(File::open(&pkg_prefs).unwrap()).unwrap();
+    if target.contains("uwp") {
+        // Assuming Hololens build
+        let to_merge = pkg_prefs
+            .as_object()
+            .unwrap()
+            .get("hololens")
+            .unwrap()
+            .as_object()
+            .unwrap();
+        for (key, value) in to_merge.iter() {
+            prefs
+                .as_object_mut()
+                .unwrap()
+                .insert(key.clone(), value.clone());
+        }
+    }
+    let file = File::create(&dest.join("prefs.json")).unwrap();
+    serde_json::to_writer(file, &prefs).unwrap();
 }

ports/libsimpleservo/api/src/lib.rs

@@ -227,22 +227,20 @@ pub fn init(
 ) -> Result<(), &'static str> {
     resources::set(Box::new(ResourceReaderInstance::new()));
 
-    let mut args = mem::replace(&mut init_opts.args, vec![]);
+    set_pref!(
-    if !args.is_empty() {
+        gfx.subpixel_text_antialiasing.enabled,
-        // opts::from_cmdline_args expects the first argument to be the binary name.
+        init_opts.enable_subpixel_text_antialiasing
-        args.insert(0, "servo".to_string());
+    );
-
-        set_pref!(
-            gfx.subpixel_text_antialiasing.enabled,
-            init_opts.enable_subpixel_text_antialiasing
-        );
-        opts::from_cmdline_args(Options::new(), &args);
-    }
 
     if let Some(prefs) = init_opts.prefs {
         add_user_prefs(prefs);
     }
 
+    let mut args = mem::replace(&mut init_opts.args, vec![]);
+    // opts::from_cmdline_args expects the first argument to be the binary name.
+    args.insert(0, "servo".to_string());
+    opts::from_cmdline_args(Options::new(), &args);
+
     let pref_url = ServoUrl::parse(&pref!(shell.homepage)).ok();
     let blank_url = ServoUrl::parse("about:blank").ok();
 
@@ -943,7 +941,7 @@ impl ResourceReaderInstance {
 impl ResourceReaderMethods for ResourceReaderInstance {
     fn read(&self, res: Resource) -> Vec<u8> {
         Vec::from(match res {
-            Resource::Preferences => &include_bytes!("../../../../resources/prefs.json")[..],
+            Resource::Preferences => &include_bytes!(concat!(env!("OUT_DIR"), "/prefs.json"))[..],
             Resource::HstsPreloadList => {
                 &include_bytes!("../../../../resources/hsts_preload.json")[..]
             },

resources/package-prefs.json

@@ -5,6 +5,12 @@
   "linux": {},
   "android": {},
   "windows": {},
+  "hololens": {
+    "_comment": "settings specific to Hololens/UWP builds",
+    "devtools.server.enabled": true,
+    "dom.webxr.enabled": true,
+    "shell.homepage": "https://servo.org/hl-home/"
+  },
   "vr": {
     "_comment": "settings specific to VR builds",
     "dom.webvr.enabled": true,

resources/prefs.json

@@ -1,4 +1,6 @@
 {
+  "devtools.server.enabled": false,
+  "devtools.server.port": 0,
   "dom.bluetooth.enabled": false,
   "dom.bluetooth.testing.enabled": false,
   "dom.canvas_capture.enabled": false,