Editorial: use tuple syntax

And consistify callsite of no-CORS-safelisted request-header.

Author: annevk

fetch.bs

@@ -1043,14 +1043,15 @@ is a <a>byte-case-insensitive</a> match for one of
  <li>`<code>Content-Type</code>`
 </ul>
 
-<p>To determine whether a <a for/>header</a> <var>header</var> is a
+<p>To determine whether a <a for/>header</a> (<var>name</var>, <var>value</var>) is a
 <dfn noexport>no-CORS-safelisted request-header</dfn>, run these steps:
 
 <ol>
- <li><p>If <var>header</var>'s <a for=header>name</a> is not a
- <a>no-CORS-safelisted request-header name</a>, then return false.
+ <li><p>If <var>name</var> is not a <a>no-CORS-safelisted request-header name</a>, then return
+ false.
 
- <li><p>Return whether <var>header</var> is a <a>CORS-safelisted request-header</a>.
+ <li><p>Return whether (<var>name</var>, <var>value</var>) is a
+ <a>CORS-safelisted request-header</a>.
 </ol>
 
 <p>A <dfn export>forbidden header name</dfn> is a <a for=/>header name</a> that is a
@@ -6383,7 +6384,7 @@ new Headers(meta2);
    <li><p>Otherwise, set <var>temporaryValue</var> to <var>temporaryValue</var>, followed by
    0x2C 0x20, followed by <var>value</var>.
 
-   <li><p>If <var>name</var>/<var>temporaryValue</var> is not a
+   <li><p>If (<var>name</var>, <var>temporaryValue</var>) is not a
    <a>no-CORS-safelisted request-header</a>, then return.
   </ol>
 
@@ -6509,7 +6510,7 @@ method steps are:
  <var>name</var> is a <a>forbidden header name</a>, return.
 
  <li><p>Otherwise, if <a>this</a>'s <a for=Headers>guard</a> is "<code>request-no-cors</code>" and
- <var>name</var>/<var>value</var> is not a <a>no-CORS-safelisted request-header</a>, return.
+ (<var>name</var>, <var>value</var>) is not a <a>no-CORS-safelisted request-header</a>, return.
 
  <li><p>Otherwise, if <a>this</a>'s <a for=Headers>guard</a> is "<code>response</code>" and
  <var>name</var> is a <a>forbidden response-header name</a>, return.