Added null check to avoid errors with passing null to a count parameter (zf1#1)

* Added null check to avoid errors with passing null to a count parameter

* treated _count as 0 in case of _file being null to avoid 7.2 count error

Author: Robbt

library/Zend/Validate/File/Count.php

@@ -253,16 +253,13 @@ public function isValid($value, $file = null)
         if (($file === null) || !empty($file['tmp_name'])) {
             $this->addFile($value);
         }
-
-        $this->_count = count($this->_files);
+        $this->_count = $this->_files !== null ? count($this->_files) : 0;
         if (($this->_max !== null) && ($this->_count > $this->_max)) {
             return $this->_throw($file, self::TOO_MANY);
         }
-
         if (($this->_min !== null) && ($this->_count < $this->_min)) {
             return $this->_throw($file, self::TOO_FEW);
         }
-
         return true;
     }