Make Window::scroll_offsets store keys as OpaqueNode values

This is the type that is supposed to signal that we will never ever
try to get back a Node from it in an unsafe way, unlike
UntrustedNodeAddress.

components/script/dom/bindings/trace.rs

@@ -115,6 +115,7 @@ use std::sync::{Arc, Mutex};
 use std::time::{Instant, SystemTime};
 use style::attr::{AttrIdentifier, AttrValue, LengthOrPercentageOrAuto};
 use style::context::QuirksMode;
+use style::dom::OpaqueNode;
 use style::element_state::*;
 use style::media_queries::MediaList;
 use style::properties::PropertyDeclarationBlock;
@@ -418,7 +419,7 @@ unsafe_no_jsmanaged_fields!(BufferQueue, QuirksMode, StrTendril);
 unsafe_no_jsmanaged_fields!(Runtime);
 unsafe_no_jsmanaged_fields!(HeaderMap, Method);
 unsafe_no_jsmanaged_fields!(WindowProxyHandler);
-unsafe_no_jsmanaged_fields!(UntrustedNodeAddress);
+unsafe_no_jsmanaged_fields!(UntrustedNodeAddress, OpaqueNode);
 unsafe_no_jsmanaged_fields!(LengthOrPercentageOrAuto);
 unsafe_no_jsmanaged_fields!(RGBA);
 unsafe_no_jsmanaged_fields!(StorageType);

components/script/dom/window.rs

@@ -102,7 +102,7 @@ use script_layout_interface::{PendingImageState, TrustedNodeAddress};
 use script_traits::webdriver_msg::{WebDriverJSError, WebDriverJSResult};
 use script_traits::{ConstellationControlMsg, DocumentState, LoadData};
 use script_traits::{ScriptMsg, ScriptToConstellationChan, ScrollState, TimerEvent, TimerEventId};
-use script_traits::{TimerSchedulerMsg, UntrustedNodeAddress, WindowSizeData, WindowSizeType};
+use script_traits::{TimerSchedulerMsg, WindowSizeData, WindowSizeType};
 use selectors::attr::CaseSensitivity;
 use servo_config::opts;
 use servo_geometry::{f32_rect_to_au_rect, MaxRect};
@@ -119,6 +119,7 @@ use std::mem;
 use std::rc::Rc;
 use std::sync::atomic::Ordering;
 use std::sync::{Arc, Mutex};
+use style::dom::OpaqueNode;
 use style::error_reporting::{ContextualParseError, ParseErrorReporter};
 use style::media_queries;
 use style::parser::ParserContext as CssParserContext;
@@ -247,7 +248,7 @@ pub struct Window {
     error_reporter: CSSErrorReporter,
 
     /// A list of scroll offsets for each scrollable element.
-    scroll_offsets: DomRefCell<HashMap<UntrustedNodeAddress, Vector2D<f32>>>,
+    scroll_offsets: DomRefCell<HashMap<OpaqueNode, Vector2D<f32>>>,
 
     /// All the MediaQueryLists we need to update
     media_query_lists: DOMTracker<MediaQueryList>,
@@ -389,7 +390,7 @@ impl Window {
     /// Sets a new list of scroll offsets.
     ///
     /// This is called when layout gives us new ones and WebRender is in use.
-    pub fn set_scroll_offsets(&self, offsets: HashMap<UntrustedNodeAddress, Vector2D<f32>>) {
+    pub fn set_scroll_offsets(&self, offsets: HashMap<OpaqueNode, Vector2D<f32>>) {
         *self.scroll_offsets.borrow_mut() = offsets
     }
 
@@ -1601,11 +1602,7 @@ impl Window {
     }
 
     pub fn scroll_offset_query(&self, node: &Node) -> Vector2D<f32> {
-        if let Some(scroll_offset) = self
+        if let Some(scroll_offset) = self.scroll_offsets.borrow().get(&node.to_opaque()) {
-            .scroll_offsets
-            .borrow()
-            .get(&node.to_untrusted_node_address())
-        {
             return *scroll_offset;
         }
         Vector2D::new(0.0, 0.0)
@@ -1620,10 +1617,9 @@ impl Window {
         // The scroll offsets are immediatly updated since later calls
         // to topScroll and others may access the properties before
         // webrender has a chance to update the offsets.
-        self.scroll_offsets.borrow_mut().insert(
+        self.scroll_offsets
-            node.to_untrusted_node_address(),
+            .borrow_mut()
-            Vector2D::new(x_ as f32, y_ as f32),
+            .insert(node.to_opaque(), Vector2D::new(x_ as f32, y_ as f32));
-        );
 
         let NodeScrollIdResponse(scroll_id) = self.layout_rpc.node_scroll_id();
 

components/script/script_thread.rs

@@ -146,6 +146,7 @@ use std::result::Result;
 use std::sync::Arc;
 use std::thread;
 use std::time::{Duration, SystemTime};
+use style::dom::OpaqueNode;
 use style::thread_state::{self, ThreadState};
 use time::{at_utc, get_time, precise_time_ns, Timespec};
 use url::percent_encoding::percent_decode;
@@ -1914,7 +1915,7 @@ impl ScriptThread {
             if node_address == UntrustedNodeAddress(ptr::null()) {
                 window.update_viewport_for_scroll(-scroll_offset.x, -scroll_offset.y);
             } else {
-                scroll_offsets.insert(node_address, -*scroll_offset);
+                scroll_offsets.insert(OpaqueNode(node_address.0 as usize), -*scroll_offset);
             }
         }
         window.set_scroll_offsets(scroll_offsets)