Resolves: tdf#118161 use ScCellIterator::isEmpty() for COUNTA()

... instead of hasEmptyData() that considers inherited svEmptyCell
as well.

Effectively a regression from

    commit 0e9e3be6
    CommitDate: Tue Mar 26 01:41:17 2013 -0400

	More on ScCellIterator usage migration.

that started to include mpCurFormula->IsEmpty() in
ScCellIterator::isEmpty() which later was renamed to
ScCellIterator::hasEmptyData() and isEmpty() introduced for real
empty.

Change-Id: Iec97d58080016c28bc9a7e47d056e4d301263928
(cherry picked from commit cfe2e4eb)
Reviewed-on: https://gerrit.libreoffice.org/55804
Tested-by: Jenkins
Reviewed-by: Kohei Yoshida <libreoffice@kohei.us>

sc/source/core/tool/interpr6.cxx

@@ -809,7 +809,7 @@ void ScInterpreter::IterateParameters( ScIterFunc eFunc, bool bTextAsZero )
                     ScCellIterator aIter( pDok, aRange, mnSubTotalFlags );
                     for (bool bHas = aIter.first(); bHas; bHas = aIter.next())
                     {
-                        if ( !aIter.hasEmptyData() )
+                        if ( !aIter.isEmpty() )
                         {
                             ++nCount;
                         }