tdf#117007 - Elementary not appearing on some backends

unity & mate added in iconthemeselector

Change-Id: I9a10af148b405068726645940d482c89962fec5c
Reviewed-on: https://gerrit.libreoffice.org/52880Reviewed-by: Heiko Tietze <tietze.heiko@gmail.com>
Tested-by: Heiko Tietze <tietze.heiko@gmail.com>

vcl/source/app/IconThemeSelector.cxx

@@ -56,7 +56,10 @@ IconThemeSelector::GetIconThemeForDesktopEnvironment(const OUString& desktopEnvi
          desktopEnvironment.equalsIgnoreAsciiCase("macosx") ) {
         r = "breeze";
     }
-    else if ( desktopEnvironment.equalsIgnoreAsciiCase("gnome") ) {
+    else
+    if ( desktopEnvironment.equalsIgnoreAsciiCase("gnome") ||
+         desktopEnvironment.equalsIgnoreAsciiCase("mate") ||
+         desktopEnvironment.equalsIgnoreAsciiCase("unity") ) {
         r = "elementary";
     }
     else {