electron: (mostly) remove dependency on libXss.so

Electron 10, which is built from Chromium 85.0.4183.84, no longer
depends on libXScrnSaver. This was removed from Chromium upstream in
revision 782094
(https://chromium-review.googlesource.com/c/chromium/src/+/2261490),
which landed in Chromium 85.0.4182.0
(https://storage.googleapis.com/chromium-find-releases-static/aa5.html#aa5c637805cd33366f2181ed6ec54e0ed174a6f9).

This change removes the LD_PRELOAD of libXss.so.1 and simply includes
libXScrnSaver in the rpath for Electron versions prior to 10.0.0.

pkgs/development/tools/electron/generic.nix

@@ -63,6 +63,7 @@ let
   electronLibPath = with lib; makeLibraryPath (
     [ libuuid at-spi2-atk at-spi2-core libappindicator-gtk3 ]
     ++ optionals (versionAtLeast version "9.0.0") [ libdrm mesa ]
+    ++ optionals (versionOlder version "10.0.0") [ libXScrnSaver ]
     ++ optionals (versionAtLeast version "11.0.0") [ libxkbcommon ]
     ++ optionals (versionAtLeast version "12.0.0") [ libxshmfence ]
     ++ optionals (versionAtLeast version "17.0.0") [ libglvnd ]
@@ -95,9 +96,7 @@ let
         $out/lib/electron/electron \
         ${lib.optionalString (lib.versionAtLeast version "15.0.0") "$out/lib/electron/chrome_crashpad_handler" }
 
-      wrapProgram $out/lib/electron/electron \
-        --prefix LD_PRELOAD : ${lib.makeLibraryPath [ libXScrnSaver ]}/libXss.so.1 \
-        "''${gappsWrapperArgs[@]}"
+      wrapProgram $out/lib/electron/electron "''${gappsWrapperArgs[@]}"
     '';
   };