Description:
------------
Similar to Bug?#28435 which should not be closed. 

Can not access results from array_count_values when 
counting strings which happen to be numbers. 

Reproduce code:
---------------
$items1 = array (1,2,2,3,3,3);
$hist1  = array_count_values ($items1);
print  "\nworks: ".join(",", $hist1);
print  "\nworks: ".$hist1[1].",".$hist1[2].",".$hist1[3];
print  "\nworks: ".$hist1["1"].",".$hist1["2"].",".$hist1["3"];


$items2 = array ("1","2","2","3","3","3","z","z");
$hist2  = array_count_values ($items2);
print  "\nworks: ".join(",", $hist2);
print  "\nfails: ".$hist2[1].",".$hist2[2].",".$hist2[3];
print  "\nfails: ".$hist2["1"].",".$hist2["2"].",".$hist2["3"].",".$hist2["z"];

print "\n\n";
var_dump($hist1);
var_dump($hist2);

Expected result:
----------------
works: 1,2,3
works: 1,2,3
works: 1,2,3
works: 1,2,3,2
fails: ,,
fails: ,,,2

Actual result:
--------------
works: 1,2,3
works: 1,2,3
works: 1,2,3
works: 1,2,3,2
fails: 1,2,3
fails: 1,2,3,2