tdf#154773 Fix Symbols dialog in dark mode

Change-Id: I92029f1d19c7545a4122b125ae69ab5964e562d2
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/150209
Tested-by: Jenkins
Reviewed-by: Heiko Tietze <heiko.tietze@documentfoundation.org>

starmath/source/dialog.cxx

@@ -61,8 +61,8 @@ void lclGetSettingColors(Color& rBackgroundColor, Color& rTextColor)
     }
     else
     {
-        rBackgroundColor = COL_WHITE;
-        rTextColor = COL_BLACK;
+        rBackgroundColor = rStyleSettings.GetFaceColor();
+        rTextColor = rStyleSettings.GetLabelTextColor();
     }
 }