accessibility: fix leak of AccessibleListBoxEntry

The problem is that AccessibleListBoxEntry from the Stylist in the
sidebar are not deleted until the document is closed, which causes
slowdowns because it causes an ever-growing list of window listeners.

There are several issues here:

* AccessibleListBoxEntry::m_aParent appears of dubious merit because
SvTreeList::Move may move entries to a different parent;
this member may or may not be initialised depending on where
the instance is created; there are confusing comments mentioning a
"Solution" but not the corresponding problem; just remove it and let
it do a dynamic lookup when needed

* AccessibleListBox::m_mapEntry already exists but is used in only half
the places where AccessibleListBoxEntry are created; use it everywhere
(consistently create entry without a parent, see previous point), and
let AccessibleListBoxEntry know the AccessibleListBox instance so it
can use the m_mapEntry too

* When VclEventId::ListboxItemRemoved event is received, the m_mapEntry
is cleared but the AccessibleListBoxEntry survive this happily;
better dispose them
(seeing as this event is regularly sent because there's some timer
clearing the Stylist and recreating it from scratch...)

Change-Id: I6c3336e019e873fa7cc8fa03cb8949a1ff2fe8fa
Reviewed-on: https://gerrit.libreoffice.org/79100
Tested-by: Jenkins
Reviewed-by: Michael Stahl <michael.stahl@cib.de>

2 files changed, 12 insertions, 9 deletions

diff --git a/accessibility/inc/extended/accessiblelistbox.hxx b/accessibility/inc/extended/accessiblelistbox.hxx
index cb075f299bb6..70248208ec0a 100644
--- a/accessibility/inc/extended/accessiblelistbox.hxx
+++ b/accessibility/inc/extended/accessiblelistbox.hxx
@@ -75,6 +75,8 @@ namespace accessibility
         AccessibleListBox( SvTreeListBox const & _rListBox,
                            const css::uno::Reference< css::accessibility::XAccessible >& _xParent );
 
+        rtl::Reference<AccessibleListBoxEntry> implGetAccessible(SvTreeListEntry & rEntry);
+
         // XTypeProvider
         DECLARE_XTYPEPROVIDER()
 
@@ -108,7 +110,7 @@ namespace accessibility
 
     private:
 
-        typedef std::map< SvTreeListEntry*, css::uno::Reference< css::accessibility::XAccessible > > MAP_ENTRY;
+        typedef std::map<SvTreeListEntry*, rtl::Reference<AccessibleListBoxEntry>> MAP_ENTRY;
         MAP_ENTRY m_mapEntry;
 
         css::uno::Reference< css::accessibility::XAccessible > m_xFocusedChild;
diff --git a/accessibility/inc/extended/accessiblelistboxentry.hxx b/accessibility/inc/extended/accessiblelistboxentry.hxx
index 2d9e4fac97b1..babaf08a52b5 100644
--- a/accessibility/inc/extended/accessiblelistboxentry.hxx
+++ b/accessibility/inc/extended/accessiblelistboxentry.hxx
@@ -54,7 +54,7 @@ class SvTreeListEntry;
 
 namespace accessibility
 {
-
+    class AccessibleListBox;
 
 // class AccessibleListBoxEntry ------------------------------------------
     typedef ::cppu::WeakAggComponentImplHelper9< css::accessibility::XAccessible
@@ -84,8 +84,8 @@ namespace accessibility
         /// client id in the AccessibleEventNotifier queue
         sal_uInt32                          m_nClientId;
 
-        css::uno::WeakReference< css::accessibility::XAccessible >
-                                            m_aParent;
+        css::uno::WeakReference<css::accessibility::XAccessible> m_wListBox;
+        AccessibleListBox & m_rListBox;
 
         tools::Rectangle               GetBoundingBox_Impl() const;
         tools::Rectangle               GetBoundingBoxOnScreen_Impl() const;
@@ -121,13 +121,14 @@ namespace accessibility
         /** Ctor()
             @param  _rListBox
                 the view control
-            @param  _pEntry
+            @param  rEntry
                 the entry
-            @param  _xParent
-                is our parent accessible object
+            @param rListBox
+                the a11y object for _rListBox
         */
-        AccessibleListBoxEntry( SvTreeListBox& _rListBox, SvTreeListEntry* _pEntry,
-                                const css::uno::Reference< css::accessibility::XAccessible >& _xParent );
+        AccessibleListBoxEntry( SvTreeListBox& _rListBox,
+                                SvTreeListEntry& rEntry,
+                                AccessibleListBox & rListBox);
 
         SvTreeListEntry* GetSvLBoxEntry() const { return m_pSvLBoxEntry; }