Revert "EmptyIterator now implements Countable; fixes bug 60577"

This reverts commit 8a936e8eb938965b0daaf076c109ec60141e57a7.
Merge branch 'PHP-5.4' into PHP-5.5

* PHP-5.4:
  Revert "EmptyIterator now implements Countable; fixes bug 60577"
Merge branch 'PHP-5.5'

* PHP-5.5:
  Revert "EmptyIterator now implements Countable; fixes bug 60577"