Reacting to environment changes

components/script/dom/document.rs

@@ -392,6 +392,8 @@ pub struct Document {
     salvageable: Cell<bool>,
     /// Whether the unload event has already been fired.
     fired_unload: Cell<bool>,
+    /// List of responsive images
+    responsive_images: DomRefCell<Vec<Dom<HTMLImageElement>>>,
 }
 
 #[derive(JSTraceable, MallocSizeOf)]
@@ -2221,6 +2223,23 @@ impl Document {
         let counter = self.throw_on_dynamic_markup_insertion_counter.get();
         self.throw_on_dynamic_markup_insertion_counter.set(counter - 1);
     }
+
+    pub fn react_to_environment_changes(&self) {
+        for image in self.responsive_images.borrow().iter() {
+            image.react_to_environment_changes();
+        }
+    }
+
+    pub fn register_responsive_image(&self, img: &HTMLImageElement) {
+        self.responsive_images.borrow_mut().push(Dom::from_ref(img));
+    }
+
+    pub fn unregister_responsive_image(&self, img: &HTMLImageElement) {
+        let index = self.responsive_images.borrow().iter().position(|x| **x == *img);
+        if let Some(i) = index {
+            self.responsive_images.borrow_mut().remove(i);
+        }
+    }
 }
 
 #[derive(MallocSizeOf, PartialEq)]
@@ -2465,7 +2484,8 @@ impl Document {
             throw_on_dynamic_markup_insertion_counter: Cell::new(0),
             page_showing: Cell::new(false),
             salvageable: Cell::new(true),
-            fired_unload: Cell::new(false)
+            fired_unload: Cell::new(false),
+            responsive_images: Default::default()
         }
     }
 

components/script/dom/window.rs

@@ -1853,6 +1853,7 @@ impl Window {
                                                  mql.Matches());
             event.upcast::<Event>().fire(mql.upcast::<EventTarget>());
         }
+        self.Document().react_to_environment_changes();
     }
 
     /// Slow down/speed up timers based on visibility.

tests/wpt/metadata/html/semantics/embedded-content/the-img-element/current-pixel-density/basic.html.ini

@@ -1,17 +1,11 @@
 [basic.html]
   type: testharness
-  [<img srcset="/images/green-256x256.png 1x" data-expect="256">]
-    expected: FAIL
-
   [<img srcset="/images/green-256x256.png 1.6x" data-expect="160">]
     expected: FAIL
 
   [<img srcset="/images/green-256x256.png 2x" data-expect="128">]
     expected: FAIL
 
-  [<img srcset="/images/green-256x256.png 256w" sizes="256px" data-expect="256">]
-    expected: FAIL
-
   [<img srcset="/images/green-256x256.png 512w" sizes="256px" data-expect="128">]
     expected: FAIL
 
@@ -30,3 +24,9 @@
   [<img srcset="data:image/svg+xml,<svg%20xmlns='http://www.w3.org/2000/svg'%20viewBox='-1%20-1%202%202'%20height='20'><circle%20r='1'/></svg> 2x" data-expect="10">]
     expected: FAIL
 
+  [<img srcset="/images/green-256x256.png 10000x" data-expect="0">]
+    expected: FAIL
+
+  [<img srcset="/images/green-256x256.png 256w" sizes="0px" data-expect="0">]
+    expected: FAIL
+

tests/wpt/metadata/html/semantics/embedded-content/the-img-element/environment-changes/viewport-change.html.ini

@@ -1,24 +1,12 @@
 [viewport-change.html]
   type: testharness
   expected: TIMEOUT
-  [img (srcset 1 cand) broken image, onload, narrow]
-    expected: FAIL
-
-  [img (srcset 1 cand) valid image, onload, narrow]
-    expected: FAIL
-
   [picture: source (max-width:500px) broken image, img valid image, resize to wide]
     expected: TIMEOUT
 
   [picture: source (max-width:500px) valid image, img valid image, resize to wide]
     expected: TIMEOUT
 
-  [img (srcset 1 cand) broken image, onload, wide]
-    expected: FAIL
-
-  [img (srcset 1 cand) valid image, onload, wide]
-    expected: FAIL
-
   [picture: source (max-width:500px) valid image, img broken image, resize to narrow]
     expected: TIMEOUT