2 files changed, 21 insertions, 1 deletions
diff --git a/components/script_layout_interface/lib.rs b/components/script_layout_interface/lib.rs
index 87b76763d7d..1793e06909d 100644
--- a/components/script_layout_interface/lib.rs
+++ b/components/script_layout_interface/lib.rs
@@ -43,6 +43,9 @@ use canvas_traits::CanvasMsg;
 use core::nonzero::NonZero;
 use ipc_channel::ipc::IpcSender;
 use libc::c_void;
+use net_traits::image_cache_thread::PendingImageId;
+use script_traits::UntrustedNodeAddress;
+use servo_url::ServoUrl;
 use std::sync::atomic::AtomicIsize;
 use style::data::ElementData;
 
@@ -137,3 +140,18 @@ pub fn is_image_data(uri: &str) -> bool {
     static TYPES: &'static [&'static str] = &["data:image/png", "data:image/gif", "data:image/jpeg"];
     TYPES.iter().any(|&type_| uri.starts_with(type_))
 }
+
+/// Whether the pending image needs to be fetched or is waiting on an existing fetch.
+pub enum PendingImageState {
+    Unrequested(ServoUrl),
+    PendingResponse,
+}
+
+/// The data associated with an image that is not yet present in the image cache.
+/// Used by the script thread to hold on to DOM elements that need to be repainted
+/// when an image fetch is complete.
+pub struct PendingImage {
+    pub state: PendingImageState,
+    pub node: UntrustedNodeAddress,
+    pub id: PendingImageId,
+}
diff --git a/components/script_layout_interface/rpc.rs b/components/script_layout_interface/rpc.rs
index 2fb75f6b959..78e99571ee7 100644
--- a/components/script_layout_interface/rpc.rs
+++ b/components/script_layout_interface/rpc.rs
@@ -2,6 +2,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
+use PendingImage;
 use app_units::Au;
 use euclid::point::Point2D;
 use euclid::rect::Rect;
@@ -37,7 +38,8 @@ pub trait LayoutRPC {
     fn offset_parent(&self) -> OffsetParentResponse;
     /// Query layout for the resolve values of the margin properties for an element.
     fn margin_style(&self) -> MarginStyleResponse;
-
+    /// Requests the list of not-yet-loaded images that were encountered in the last reflow.
+    fn pending_images(&self) -> Vec<PendingImage>;
     fn nodes_from_point(&self, page_point: Point2D<f32>, client_point: Point2D<f32>) -> Vec<UntrustedNodeAddress>;
 
     fn text_index(&self) -> TextIndexResponse;