qtwebchannel init at 5.6.1-1

pkgs/development/libraries/qt-5/5.6/default.nix

···
       qttools = callPackage ./qttools.nix {};
       qttranslations = callPackage ./qttranslations.nix {};
       /* qtwayland = not packaged */
-      /* qtwebchannel = not packaged */
+      qtwebchannel = callPackage ./qtwebchannel.nix {};
       /* qtwebengine = not packaged */
       qtwebsockets = callPackage ./qtwebsockets.nix {};
       /* qtwinextras = not packaged */

pkgs/development/libraries/qt-5/5.6/qtwebchannel.nix

···
+{ qtSubmodule, qtbase, qtdeclarative }:
+
+qtSubmodule {
+  name = "qtwebchannel";
+  qtInputs = [ qtbase qtdeclarative ];
+}
+