use forward declaration for SfxItemSet

Change-Id: I81f5d1ca22868d278662a55443e2038581dd3246
Reviewed-on: https://gerrit.libreoffice.org/35280
Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>

basctl/source/basicide/basdoc.cxx

@@ -27,6 +27,7 @@
 #define basctl_DocShell     // This CANNOT come before basdoc apparently
 #include <basslots.hxx>
 #include <sfx2/sfxmodelfactory.hxx>
+#include <svl/itemset.hxx>
 #include <svx/svxids.hrc>
 #include <tools/globname.hxx>
 

include/editeng/editobj.hxx

@@ -21,7 +21,6 @@
 #define INCLUDED_EDITENG_EDITOBJ_HXX
 
 #include <rsc/rscsfx.hxx>
-#include <svl/itemset.hxx>
 #include <svl/itempool.hxx>
 #include <editeng/eeitem.hxx>
 #include <editeng/editdata.hxx>
@@ -34,7 +33,7 @@
 #include <vector>
 #include <memory>
 
-class SfxItemPool;
+class SfxItemSet;
 class SfxStyleSheetPool;
 class SvxFieldItem;
 class SvxFieldData;

include/sfx2/itemconnect.hxx

@@ -25,6 +25,7 @@
 #include <sfx2/dllapi.h>
 #include <sfx2/itemwrapper.hxx>
 #include <sfx2/controlwrapper.hxx>
+#include <svl/itemset.hxx>
 #include <memory>
 
 

include/sfx2/itemwrapper.hxx

@@ -23,10 +23,9 @@
 #include <sal/config.h>
 #include <sfx2/dllapi.h>
 #include <svl/eitem.hxx>
-#include <svl/stritem.hxx>
 #include <svl/intitem.hxx>
-#include <svl/itemset.hxx>
 
+class SfxItemSet;
 
 namespace sfx {
 

include/sfx2/msg.hxx

@@ -23,10 +23,14 @@
 #include <rtl/string.hxx>
 #include <rtl/ustring.hxx>
 #include <sfx2/dllapi.h>
-#include <svl/itemset.hxx>
 #include <o3tl/typed_flags_set.hxx>
 #include <functional>
 
+class SfxItemPool;
+class SfxItemSet;
+class SfxPoolItem;
+class SfxRequest;
+
 enum class SfxSlotMode {
     NONE            =    0x0000L, // default
 
@@ -56,9 +60,6 @@ namespace o3tl
     template<> struct typed_flags<SfxSlotMode> : is_typed_flags<SfxSlotMode, 0x13ec72cL> {};
 }
 
-
-class SfxRequest;
-
 #define SFX_EXEC_STUB( aShellClass, aExecMethod) \
  void SfxStub##aShellClass##aExecMethod( \
    SfxShell *pShell, SfxRequest& rReq) \
@@ -94,7 +95,7 @@ struct SfxTypeAttrib
     sal_uInt16                  nAID;
     const char* pName;
 };
-class SfxPoolItem;
+
 template<class T> SfxPoolItem* createSfxPoolItem()
 {
     return T::CreateDefault();

include/svx/EnhancedCustomShape2d.hxx

@@ -42,7 +42,6 @@
 class Color;
 class SdrObject;
 class SdrPathObj;
-class SfxItemSet;
 
 enum class HandleFlags
 {

include/svx/fntctrl.hxx

@@ -23,7 +23,6 @@
 #include <editeng/svxfont.hxx>
 #include <svx/svxdllapi.h>
 #include <svl/itempool.hxx>
-#include <svl/itemset.hxx>
 
 #include <rtl/ustring.hxx>
 

sc/source/filter/excel/xeescher.cxx

@@ -56,6 +56,7 @@
 #include "xestyle.hxx"
 #include "userdat.hxx"
 #include "drwlayer.hxx"
+#include <svl/itemset.hxx>
 #include <svx/unoapi.hxx>
 #include <svx/algitem.hxx>
 #include "scitems.hxx"

svx/source/customshapes/EnhancedCustomShapeFontWork.cxx

@@ -18,6 +18,7 @@
  */
 
 #include "EnhancedCustomShapeFontWork.hxx"
+#include <svl/itemset.hxx>
 #include <svx/svddef.hxx>
 #include <svx/svdogrp.hxx>
 #include <svx/svdopath.hxx>

sw/inc/SwAppletImpl.hxx

@@ -36,9 +36,6 @@ enum class SwHtmlOptType {
     SIZE = 3
 };
 
-
-class SfxItemSet;
-
 #define OOO_STRING_SW_HTML_O_Hidden "HIDDEN"
 
 class SwApplet_Impl