From 0701c0c9530dbb8381c5c43d96d8c0e3c98b0dd0 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Emilio=20Cobos=20=C3=81lvarez?= <emilio@crisal.io>
Date: Mon, 21 Aug 2017 20:17:24 +0200
Subject: [PATCH] style: Add docs about the lack of device in the stylesheet
 set.

Also add a few comments and similar about pending invalidation work, and avoid
passing a device in script, since the work it performs scanning the stylesheet
is just thrown away in the `flush_without_invalidations` call.
---
 components/script/dom/document.rs  | 13 ++++++++-----
 components/style/stylesheet_set.rs |  2 ++
 2 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/components/script/dom/document.rs b/components/script/dom/document.rs
index 3105f0f4341..4629ff8814f 100644
--- a/components/script/dom/document.rs
+++ b/components/script/dom/document.rs
@@ -2338,6 +2338,11 @@ impl Document {
     pub fn flush_stylesheets_for_reflow(&self) -> bool {
         // NOTE(emilio): The invalidation machinery is used on the replicated
         // list on the layout thread.
+        //
+        // FIXME(emilio): This really should differentiate between CSSOM changes
+        // and normal stylesheets additions / removals, because in the last case
+        // the layout thread already has that information and we could avoid
+        // dirtying the whole thing.
         let mut stylesheets = self.stylesheets.borrow_mut();
         let have_changed = stylesheets.has_changed();
         stylesheets.flush_without_invalidation();
@@ -2370,11 +2375,10 @@ impl Document {
             .unwrap();
 
         let guard = s.shared_lock.read();
-        let device = self.device();
 
         // FIXME(emilio): Would be nice to remove the clone, etc.
         self.stylesheets.borrow_mut().remove_stylesheet(
-            device.as_ref(),
+            None,
             StyleSheetInDocument {
                 sheet: s.clone(),
                 owner: JS::from_ref(owner),
@@ -2414,13 +2418,12 @@ impl Document {
         let lock = self.style_shared_lock();
         let guard = lock.read();
 
-        let device = self.device();
         match insertion_point {
             Some(ip) => {
-                stylesheets.insert_stylesheet_before(device.as_ref(), sheet, ip, &guard);
+                stylesheets.insert_stylesheet_before(None, sheet, ip, &guard);
             }
             None => {
-                stylesheets.append_stylesheet(device.as_ref(), sheet, &guard);
+                stylesheets.append_stylesheet(None, sheet, &guard);
             }
         }
     }
diff --git a/components/style/stylesheet_set.rs b/components/style/stylesheet_set.rs
index 795aa60fea7..91e87cff239 100644
--- a/components/style/stylesheet_set.rs
+++ b/components/style/stylesheet_set.rs
@@ -106,6 +106,8 @@ where
     }
 
     /// Appends a new stylesheet to the current set.
+    ///
+    /// No device implies not computing invalidations.
     pub fn append_stylesheet(
         &mut self,
         device: Option<&Device>,