Add nonce for Safari 12+

As far as I can tell this should work now.

Signed-off-by: Roeland Jago Douma <roeland@famdouma.nl>

lib/private/Security/CSP/ContentSecurityPolicyNonceManager.php

@@ -74,6 +74,8 @@ class ContentSecurityPolicyNonceManager {
 			Request::USER_AGENT_CHROME,
 			// Firefox 45+
 			'/^Mozilla\/5\.0 \([^)]+\) Gecko\/[0-9.]+ Firefox\/(4[5-9]|[5-9][0-9])\.[0-9.]+$/',
+			// Safari 12+
+			'/^Mozilla\/5\.0 \([^)]+\) AppleWebKit\/[0-9.]+ \(KHTML, like Gecko\) Version\/(1[2-9]|[2-9][0-9])\.[0-9]+ Safari\/[0-9.A-Z]+$/',
 		];
 
 		if($this->request->isUserAgent($browserWhitelist)) {