Backport fix from php-mime-mail-parser to fix attachment parsing

Summary:
- Allow proper parsing of attachments with missing Content-Disposition
  header

Test Plan:
- Create application email for Maniphest.
- Send example broken email from Outlook 2007 to that address {F1842816}

Reviewers: #blessed_reviewers, epriestley

Reviewed By: #blessed_reviewers, epriestley

Subscribers: epriestley

Differential Revision: https://secure.phabricator.com/D16584

externals/mimemailparser/MimeMailParser.class.php

@@ -251,20 +251,42 @@ class MimeMailParser {
 		return $headers;
 	}
 
-
 	/**
 	 * Returns the attachments contents in order of appearance
 	 * @return Array
 	 * @param $type Object[optional]
 	 */
 	public function getAttachments() {
+    // NOTE: This has been modified for Phabricator. Some mail clients do not
+    // send attachments with "Content-Disposition" headers.
 		$attachments = array();
 		$dispositions = array("attachment","inline");
+		$non_attachment_types = array("text/plain", "text/html");
+		$nonameIter = 0;
 		foreach ($this->parts as $part) {
 			$disposition = $this->getPartContentDisposition($part);
-			if (in_array($disposition, $dispositions)) {
+			$filename = 'noname';
+			if (isset($part['disposition-filename'])) {
+				$filename = $part['disposition-filename'];
+			} elseif (isset($part['content-name'])) {
+				// if we have no disposition but we have a content-name, it's a valid attachment.
+				// we simulate the presence of an attachment disposition with a disposition filename
+				$filename = $part['content-name'];
+				$disposition = 'attachment';
+			} elseif (!in_array($part['content-type'], $non_attachment_types, true)
+				&& substr($part['content-type'], 0, 10) !== 'multipart/'
+				) {
+				// if we cannot get it with getMessageBody, we assume it is an attachment
+				$disposition = 'attachment';
+			}
+
+			if (in_array($disposition, $dispositions) && isset($filename) === true) {
+				if ($filename == 'noname') {
+					$nonameIter++;
+					$filename = 'noname'.$nonameIter;
+				}
 				$attachments[] = new MimeMailParser_attachment(
-					$part['disposition-filename'],
+					$filename,
 					$this->getPartContentType($part),
 					$this->getAttachmentStream($part),
 					$disposition,