tdf#42982: Improve UNO API error reporting

Add more info to the exception in
AccessibleIconChoiceCtrl::getAccessibleChild()

Change-Id: Ie6e778f76719eb463508647f0367e089ab0ae8ec
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/92514
Tested-by: Jenkins
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>
diff --git a/accessibility/source/extended/accessibleiconchoicectrl.cxx b/accessibility/source/extended/accessibleiconchoicectrl.cxx
index 679a615..f521a23 100644
--- a/accessibility/source/extended/accessibleiconchoicectrl.cxx
+++ b/accessibility/source/extended/accessibleiconchoicectrl.cxx
@@ -162,7 +162,10 @@ namespace accessibility
        VclPtr<SvtIconChoiceCtrl> pCtrl = getCtrl();
        SvxIconChoiceCtrlEntry* pEntry = pCtrl->GetEntry(i);
        if ( !pEntry )
            throw RuntimeException();
            throw RuntimeException("getAccessibleChild: Entry "
                                   + OUString::number(i) + " not found",
                static_cast<css::lang::XTypeProvider*>(
                    static_cast<VCLXAccessibleComponent_BASE*>(this)));

        return new AccessibleIconChoiceCtrlEntry( *pCtrl, i, this );
    }