tdf#146619 Use more forward declarations in include/vcl/[A-Z]*

Found after running bin/find-unneeded-includes --headersfwd include/vcl/[A-Z]*

This shaves off about 100M input, not bad for such a small amount
of files checked

This time --headersfwd skips files that contain #if defs,
in hope of not breaking builds that are not checked by CI

(...except for include/vcl/BitmapTools.hxx - this was cleaned accidentally,
due to a bug in the bin/find-unneeded-includes script that is fixed
by the previous commit 930ff2b830
- but let's keep this anyway, it seems fine)

Change-Id: Ia8e49d94f6adb3cdbedbc40ffa56dbf846c9b6e4
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/196235
Reviewed-by: Gabor Kelemen <gabor.kelemen@collabora.com>
Tested-by: Jenkins

cppcanvas/source/mtfrenderer/implrenderer.cxx

@@ -54,6 +54,7 @@
 #include <vcl/metric.hxx>
 #include <vcl/graphictools.hxx>
 #include <vcl/BitmapPalette.hxx>
+#include <vcl/BitmapColor.hxx>
 #include <tools/poly.hxx>
 #include <i18nlangtag/languagetag.hxx>
 #include <implrenderer.hxx>