do not remove metadata from pdf - and commit...

wp-mat.php

@@ -26,10 +26,12 @@ class WP_Mat {
 
     // Check if the mime type is one of those we want to clean up.
     // Use a blacklist, currently empty. Send everything by default
-    // except video.
+    // except video, and pdf.
     function is_supported_mime_type($mimetype) {
         if (substr($mimetype, 0, 6) === "video/") {
             return false;
+        if (substr($mimetype, 0, 15) === "application/pdf") {
+            return false;
         }
         return true;
     }