Restore Zotero icon.

users/jrpotter/zotero.nix

@@ -129,6 +129,10 @@ stdenv.mkDerivation rec {
     # install desktop file and icons.
     mkdir -p $out/share/applications
     cp ${desktopItem}/share/applications/* $out/share/applications/
+    for size in 32 128; do
+      install -Dm444 icons/icon$size.png \
+        $out/share/icons/hicolor/''${size}x''${size}/apps/zotero.png
+    done
 
     runHook postInstall
   '';