Fix for non .php files gathered by XDebug

Author: Victor Garcia

PHP/CodeCoverage.php

@@ -459,7 +459,9 @@ protected function initializeFilesThatAreSeenTheFirstTime($data)
             // Patch for XDebug bug:
             // http://bugs.xdebug.org/bug_view_page.php?bug_id=0000331
             preg_match('/.*\.php/', $file, $matches);
-            $file = $matches[0];
+            if(isset($matches[0])) {
+                $file = $matches[0];
+            }
 
             if ($this->filter->isFile($file) && !isset($this->data[$file])) {
                 $this->data[$file] = array();