--- a/gfx/webrender_bindings/src/bindings.rs
+++ b/gfx/webrender_bindings/src/bindings.rs
@@ -283,18 +283,17 @@ pub struct WrImageDescriptor {
     pub height: u32,
     pub stride: u32,
     pub is_opaque: bool,
 }
 
 impl<'a> Into<ImageDescriptor> for &'a WrImageDescriptor {
     fn into(self) -> ImageDescriptor {
         ImageDescriptor {
-            width: self.width,
-            height: self.height,
+            size: DeviceUintSize::new(self.width, self.height),
             stride: if self.stride != 0 {
                 Some(self.stride)
             } else {
                 None
             },
             format: self.format,
             is_opaque: self.is_opaque,
             offset: 0,

--- a/gfx/webrender_bindings/src/moz2d_renderer.rs
+++ b/gfx/webrender_bindings/src/moz2d_renderer.rs
@@ -336,25 +336,25 @@ fn merge_blob_images(old_buf: &[u8], new
     assert!(old_reader.cache.is_empty());
 
     let result = result.finish();
     check_result(&result);
     result
 }
 
 impl BlobImageRenderer for Moz2dImageRenderer {
-    fn add(&mut self, key: ImageKey, data: BlobImageData, tiling: Option<TileSize>) {
+    fn add(&mut self, key: ImageKey, data: Arc<BlobImageData>, tiling: Option<TileSize>) {
         {
             let index = BlobReader::new(&data);
             assert!(index.reader.has_more());
         }
-        self.blob_commands.insert(key, (Arc::new(data), tiling));
+        self.blob_commands.insert(key, (Arc::clone(&data), tiling));
     }
 
-    fn update(&mut self, key: ImageKey, data: BlobImageData, dirty_rect: Option<DeviceUintRect>) {
+    fn update(&mut self, key: ImageKey, data: Arc<BlobImageData>, dirty_rect: Option<DeviceUintRect>) {
         match self.blob_commands.entry(key) {
             hash_map::Entry::Occupied(mut e) => {
                 let old_data = &mut e.get_mut().0;
                 *old_data = Arc::new(merge_blob_images(&old_data, &data,
                                                        dirty_rect.unwrap().into()));
             }
             _ => { panic!("missing image key"); }
         }
@@ -423,36 +423,35 @@ impl BlobImageRenderer for Moz2dImageRen
             let mut index = BlobReader::new(&commands);
             while index.reader.pos < index.reader.buf.len() {
                 let e  = index.read_entry();
                 process_fonts(BufReader::new(&commands[e.end..e.extra_end]), resources);
             }
         }
 
         self.workers.spawn(move || {
-            let buf_size = (descriptor.width
-                * descriptor.height
+            let buf_size = (descriptor.size.width
+                * descriptor.size.height
                 * descriptor.format.bytes_per_pixel()) as usize;
             let mut output = vec![0u8; buf_size];
 
             let result = unsafe {
                 if wr_moz2d_render_cb(
                     ByteSlice::new(&commands[..]),
-                    descriptor.width,
-                    descriptor.height,
+                    descriptor.size.width,
+                    descriptor.size.height,
                     descriptor.format,
                     option_to_nullable(&tile_size),
                     option_to_nullable(&request.tile),
                     option_to_nullable(&dirty_rect),
                     MutByteSlice::new(output.as_mut_slice())
                 ) {
 
                     Ok(RasterizedBlobImage {
-                        width: descriptor.width,
-                        height: descriptor.height,
+                        size: descriptor.size,
                         data: output,
                     })
                 } else {
                     panic!("Moz2D replay problem");
                 }
             };
 
             tx.send((request, result)).unwrap();