compositing: Fix a couple of bugs that prevented iframes from painting after navigation.

components/compositing/compositor.rs

@@ -790,6 +790,13 @@ impl<Window: WindowMethods> IOCompositor<Window> {
 
         match self.find_layer_with_pipeline_and_layer_id(pipeline_id, properties.id) {
             Some(existing_layer) => {
+                // If this layer contains a subpage, then create the root layer for that subpage
+                // now.
+                if properties.subpage_pipeline_id.is_some() {
+                    self.create_root_layer_for_subpage_if_necessary(properties,
+                                                                    existing_layer.clone())
+                }
+
                 existing_layer.update_layer(properties);
                 true
             }
@@ -868,32 +875,9 @@ impl<Window: WindowMethods> IOCompositor<Window> {
             }
 
             // If this layer contains a subpage, then create the root layer for that subpage now.
-            if let Some(ref subpage_pipeline_id) = layer_properties.subpage_pipeline_id {
-                let subpage_layer_properties = LayerProperties {
-                    id: LayerId::null(),
-                    parent_id: None,
-                    rect: Rect::new(Point2D::zero(), layer_properties.rect.size),
-                    background_color: layer_properties.background_color,
-                    scroll_policy: ScrollPolicy::Scrollable,
-                    transform: Matrix4::identity(),
-                    perspective: Matrix4::identity(),
-                    subpage_pipeline_id: layer_properties.subpage_pipeline_id,
-                    establishes_3d_context: true,
-                    scrolls_overflow_area: true,
-                };
-
-                let wants_scroll_events = if subpage_layer_properties.scrolls_overflow_area {
-                    WantsScrollEventsFlag::WantsScrollEvents
-                } else {
-                    WantsScrollEventsFlag::DoesntWantScrollEvents
-                };
-                let subpage_layer = CompositorData::new_layer(*subpage_pipeline_id,
-                                                              subpage_layer_properties,
-                                                              wants_scroll_events,
-                                                              new_layer.tile_size);
-                *subpage_layer.masks_to_bounds.borrow_mut() = true;
-                new_layer.add_child(subpage_layer);
-                self.pending_subpages.insert(*subpage_pipeline_id);
+            if layer_properties.subpage_pipeline_id.is_some() {
+                self.create_root_layer_for_subpage_if_necessary(layer_properties,
+                                                                new_layer.clone())
             }
 
             parent_layer.add_child(new_layer.clone());
@@ -902,6 +886,46 @@ impl<Window: WindowMethods> IOCompositor<Window> {
         self.dump_layer_tree();
     }
 
+    fn create_root_layer_for_subpage_if_necessary(&mut self,
+                                                  layer_properties: LayerProperties,
+                                                  parent_layer: Rc<Layer<CompositorData>>) {
+        if parent_layer.children
+                       .borrow()
+                       .iter()
+                       .any(|child| child.extra_data.borrow().subpage_info.is_some()) {
+            return
+        }
+
+        let subpage_pipeline_id =
+            layer_properties.subpage_pipeline_id
+                            .expect("create_root_layer_for_subpage() called for non-subpage?!");
+        let subpage_layer_properties = LayerProperties {
+            id: LayerId::null(),
+            parent_id: None,
+            rect: Rect::new(Point2D::zero(), layer_properties.rect.size),
+            background_color: layer_properties.background_color,
+            scroll_policy: ScrollPolicy::Scrollable,
+            transform: Matrix4::identity(),
+            perspective: Matrix4::identity(),
+            subpage_pipeline_id: Some(subpage_pipeline_id),
+            establishes_3d_context: true,
+            scrolls_overflow_area: true,
+        };
+
+        let wants_scroll_events = if subpage_layer_properties.scrolls_overflow_area {
+            WantsScrollEventsFlag::WantsScrollEvents
+        } else {
+            WantsScrollEventsFlag::DoesntWantScrollEvents
+        };
+        let subpage_layer = CompositorData::new_layer(subpage_pipeline_id,
+                                                      subpage_layer_properties,
+                                                      wants_scroll_events,
+                                                      parent_layer.tile_size);
+        *subpage_layer.masks_to_bounds.borrow_mut() = true;
+        parent_layer.add_child(subpage_layer);
+        self.pending_subpages.insert(subpage_pipeline_id);
+    }
+
     fn send_window_size(&self) {
         let dppx = self.page_zoom * self.device_pixels_per_screen_px();
         let initial_viewport = self.window_size.as_f32() / dppx;

components/compositing/compositor_layer.rs

@@ -211,6 +211,7 @@ pub enum ScrollEventResult {
 impl CompositorLayer for Layer<CompositorData> {
     fn update_layer_except_bounds(&self, layer_properties: LayerProperties) {
         self.extra_data.borrow_mut().scroll_policy = layer_properties.scroll_policy;
+        self.extra_data.borrow_mut().subpage_info = layer_properties.subpage_pipeline_id;
         *self.transform.borrow_mut() = layer_properties.transform;
         *self.perspective.borrow_mut() = layer_properties.perspective;
 

components/compositing/constellation.rs

@@ -1311,6 +1311,17 @@ impl<LTF: LayoutThreadFactory, STF: ScriptThreadFactory> Constellation<LTF, STF>
     fn handle_activate_document_msg(&mut self, pipeline_id: PipelineId) {
         debug!("Document ready to activate {:?}", pipeline_id);
 
+        if let Some(ref child_pipeline) = self.pipelines.get(&pipeline_id) {
+            if let Some(ref parent_info) = child_pipeline.parent_info {
+                if let Some(parent_pipeline) = self.pipelines.get(&parent_info.0) {
+                    let _ = parent_pipeline.script_chan
+                                           .send(ConstellationControlMsg::FramedContentChanged(
+                            parent_info.0,
+                            parent_info.1));
+                }
+            }
+        }
+
         // If this pipeline is already part of the current frame tree,
         // we don't need to do anything.
         if self.pipeline_is_in_current_frame(pipeline_id) {

components/script/dom/window.rs

@@ -107,6 +107,7 @@ pub enum ReflowReason {
     ImageLoaded,
     RequestAnimationFrame,
     WebFontLoaded,
+    FramedContentChanged,
 }
 
 pub type ScrollPoint = Point2D<Au>;
@@ -1425,6 +1426,7 @@ fn debug_reflow_events(goal: &ReflowGoal, query_type: &ReflowQueryType, reason:
         ReflowReason::ImageLoaded => "\tImageLoaded",
         ReflowReason::RequestAnimationFrame => "\tRequestAnimationFrame",
         ReflowReason::WebFontLoaded => "\tWebFontLoaded",
+        ReflowReason::FramedContentChanged => "\tFramedContentChanged",
     });
 
     println!("{}", debug_msg);

components/script/script_thread.rs

@@ -1127,6 +1127,8 @@ impl ScriptThread {
             ConstellationControlMsg::DispatchFrameLoadEvent {
                 target: pipeline_id, parent: containing_id } =>
                 self.handle_frame_load_event(containing_id, pipeline_id),
+            ConstellationControlMsg::FramedContentChanged(containing_pipeline_id, subpage_id) =>
+                self.handle_framed_content_changed(containing_pipeline_id, subpage_id),
             ConstellationControlMsg::ReportCSSError(pipeline_id, filename, line, column, msg) =>
                 self.handle_css_error_reporting(pipeline_id, filename, line, column, msg),
         }
@@ -1483,6 +1485,22 @@ impl ScriptThread {
         }
     }
 
+    fn handle_framed_content_changed(&self,
+                                     parent_pipeline_id: PipelineId,
+                                     subpage_id: SubpageId) {
+        let borrowed_page = self.root_page();
+        let page = borrowed_page.find(parent_pipeline_id).unwrap();
+        let doc = page.document();
+        let frame_element = doc.find_iframe(subpage_id);
+        if let Some(ref frame_element) = frame_element {
+            frame_element.upcast::<Node>().dirty(NodeDamage::OtherNodeDamage);
+            let window = page.window();
+            window.reflow(ReflowGoal::ForDisplay,
+                          ReflowQueryType::NoQuery,
+                          ReflowReason::FramedContentChanged);
+        }
+    }
+
     /// Handles a mozbrowser event, for example see:
     /// https://developer.mozilla.org/en-US/docs/Web/Events/mozbrowserloadstart
     fn handle_mozbrowser_event_msg(&self,

components/script_traits/lib.rs

@@ -143,6 +143,8 @@ pub enum ConstellationControlMsg {
         /// The pipeline that contains a frame loading the target pipeline.
         parent: PipelineId
     },
+    /// Notifies a parent frame that one of its child frames is now active.
+    FramedContentChanged(PipelineId, SubpageId),
     /// Report an error from a CSS parser for the given pipeline
     ReportCSSError(PipelineId, String, u32, u32, String),
 }

tests/wpt/mozilla/meta/MANIFEST.json

@@ -1688,6 +1688,18 @@
             "url": "/_mozilla/css/iframe/multiple_external.html"
           }
         ],
+        "css/iframe/navigation.html": [
+          {
+            "path": "css/iframe/navigation.html",
+            "references": [
+              [
+                "/_mozilla/css/iframe/navigation_ref.html",
+                "=="
+              ]
+            ],
+            "url": "/_mozilla/css/iframe/navigation.html"
+          }
+        ],
         "css/iframe/overflow.html": [
           {
             "path": "css/iframe/overflow.html",

tests/wpt/mozilla/tests/css/iframe/navigation.html

@@ -0,0 +1,36 @@
+<!DOCTYPE html>
+<html class="reftest-wait">
+<style>
+iframe {
+    display: block;
+    border: 1px solid black;
+    width: 500px;
+    height: 300px;
+    margin-left: 10px;
+    margin-top: 0px;
+}
+</style>
+<body>
+<iframe src="data:text/html,Foo"></iframe>
+<script>
+setTimeout(function() {
+    var iframe = document.getElementsByTagName('iframe')[0];
+    var navigated = false;
+    iframe.addEventListener('load', function() {
+        if (navigated) {
+            // Uncomment the following lines to observe that the navigation happens.
+            // If the lines are commented out, the test times out.
+            /*console.log("about to remove reftest-wait: document class is now: " +
+                        document.documentElement.getAttribute('class'));*/
+            document.documentElement.classList.remove("reftest-wait");
+            /*console.log("navigated: document class is now: " +
+                        document.documentElement.getAttribute('class'));*/
+        }
+    }, false);
+    iframe.src = "data:text/html,Hello%20world";
+    navigated = true;
+}, 16);
+</script>
+</body>
+</html>
+

tests/wpt/mozilla/tests/css/iframe/navigation_ref.html

@@ -0,0 +1,17 @@
+<!DOCTYPE html>
+<html>
+<style>
+iframe {
+    display: block;
+    border: 1px solid black;
+    width: 500px;
+    height: 300px;
+    margin-left: 10px;
+    margin-top: 0px;
+}
+</style>
+<body>
+<iframe src="data:text/html,Hello%20world"></iframe>
+</body>
+</html>
+