Correct an ambiguous regexp in DiffusionRequest

Summary:
See <https://discourse.phabricator-community.org/t/diffusionrequest-regex-error/2057/>.

The intent of `[\d-,]` is "digits, hyphen, and comma" but `[x-y]` means "character range x-y".

Specify `[\d,-]` instead to disambiguate the hyphen as "literal hyphen", not a character range marker.

Test Plan: I can't reproduce the original error as reported, but browsed around Diffusion for a bit.

Reviewers: amckinley, avivey

Reviewed By: avivey

Differential Revision: https://secure.phabricator.com/D19770

src/applications/diffusion/request/DiffusionRequest.php

@@ -489,7 +489,7 @@ abstract class DiffusionRequest extends Phobject {
     // Consume the back part of the URI, up to the first "$". Use a negative
     // lookbehind to prevent matching '$$'. We double the '$' symbol when
     // encoding so that files with names like "money/$100" will survive.
-    $pattern = '@(?:(?:^|[^$])(?:[$][$])*)[$]([\d-,]+)$@';
+    $pattern = '@(?:(?:^|[^$])(?:[$][$])*)[$]([\d,-]+)$@';
     if (preg_match($pattern, $blob, $matches)) {
       $result['line'] = $matches[1];
       $blob = substr($blob, 0, -(strlen($matches[1]) + 1));