Referrer Policy now defines a default constant

w3c/webappsec-referrer-policy#142 links tests and has the corresponding Referrer Policy change. whatwg/html#5783 has the corresponding change to HTML.

Author: krgovind

fetch.bs

@@ -3368,11 +3368,7 @@ optionally with a <i>recursive flag</i>, run these steps:
    <li>
     <p>If <var>request</var>'s <a for=request>referrer policy</a>
     is the empty string, then set <var>request</var>'s
-    <a for=request>referrer policy</a> to
-    "<code>no-referrer-when-downgrade</code>".
-
-    <p class="note no-backref">We use "<code>no-referrer-when-downgrade</code>" because it is the
-    historical default.
+    <a for=request>referrer policy</a> to the <a for=/>default referrer policy</a>.
 
    <li>
     <p>If <var>request</var>'s <a for=request>referrer</a>