treewide: use GST_PLUGIN_SYSTEM_PATH_1_0 instead of GST_PLUGIN_SYSTEM_PATH

When GST_PLUGIN_SYSTEM_PATH_1_0 is set, gstreamer ignores
GST_PLUGIN_SYSTEM_PATH.

pkgs/applications/audio/mopidy/mopidy.nix

@@ -38,10 +38,6 @@ pythonPackages.buildPythonApplication rec {
   # There are no tests
   doCheck = false;
 
-  preFixup = ''
-    gappsWrapperArgs+=(--prefix GST_PLUGIN_SYSTEM_PATH : "$GST_PLUGIN_SYSTEM_PATH")
-  '';
-
   meta = with stdenv.lib; {
     homepage = "https://www.mopidy.com/";
     description = ''

pkgs/applications/office/libreoffice/default.nix

@@ -300,8 +300,6 @@ in (mkDrv rec {
     cp -r sysui/desktop/icons  "$out/share"
     sed -re 's@Icon=libreoffice(dev)?[0-9.]*-?@Icon=@' -i "$out/share/applications/"*.desktop
 
-    qtWrapperArgs+=(--prefix GST_PLUGIN_SYSTEM_PATH : "$GST_PLUGIN_SYSTEM_PATH")
-
     mkdir -p $dev
     cp -r include $dev
   '' + lib.optionalString kdeIntegration ''

pkgs/development/libraries/gstreamer/core/default.nix

@@ -94,7 +94,7 @@ stdenv.mkDerivation rec {
   postInstall = ''
     for prog in "$dev/bin/"*; do
         # We can't use --suffix here due to quoting so we craft the export command by hand
-        wrapProgram "$prog" --run 'export GST_PLUGIN_SYSTEM_PATH=$GST_PLUGIN_SYSTEM_PATH''${GST_PLUGIN_SYSTEM_PATH:+:}$(unset _tmp; for profile in $NIX_PROFILES; do _tmp="$profile/lib/gstreamer-1.0''${_tmp:+:}$_tmp"; done; printf '%s' "$_tmp")'
+        wrapProgram "$prog" --run 'export GST_PLUGIN_SYSTEM_PATH_1_0=$GST_PLUGIN_SYSTEM_PATH_1_0''${GST_PLUGIN_SYSTEM_PATH_1_0:+:}$(unset _tmp; for profile in $NIX_PROFILES; do _tmp="$profile/lib/gstreamer-1.0''${_tmp:+:}$_tmp"; done; printf '%s' "$_tmp")'
     done
   '';
 

pkgs/tools/cd-dvd/brasero/default.nix

@@ -36,7 +36,7 @@ in stdenv.mkDerivation rec {
   ];
 
   preFixup = ''
-    gappsWrapperArgs+=(--prefix PATH : "${binpath}" --prefix GST_PLUGIN_SYSTEM_PATH : "$GST_PLUGIN_SYSTEM_PATH")
+    gappsWrapperArgs+=(--prefix PATH : "${binpath}")
   '';
 
   meta = with stdenv.lib; {