Review tweaks

- WAI-ARIA in non-bilbio -> ARIA
- Explain default ~ native ~ implicit ~ host language in a note
- Single quotes
- Map is initially empty

source

@@ -12837,7 +12837,7 @@ interface <dfn>DOMStringMap</dfn> {
 
   <p>User agent requirements for implementing Accessibility API semantics on <span>HTML
   elements</span> are defined in <cite>HTML Accessibility API Mappings</cite>. In addition to the
-  rules there, for a <span>custom element</span> <var>element</var>, the default WAI-ARIA role
+  rules there, for a <span>custom element</span> <var>element</var>, the default ARIA role
   semantics are determined as follows: <ref spec=HTMLAAM></p>
 
   <ol>
@@ -12850,7 +12850,7 @@ interface <dfn>DOMStringMap</dfn> {
    <li><p>Otherwise, return no role.</p></li>
   </ol>
 
-  <p>Similarly, for a <span>custom element</span> <var>element</var>, the default WAI-ARIA state and
+  <p>Similarly, for a <span>custom element</span> <var>element</var>, the default ARIA state and
   property semantics, for a state or property named <var>stateOrProperty</var>, are determined as
   follows:</p>
 
@@ -12864,6 +12864,9 @@ interface <dfn>DOMStringMap</dfn> {
    <li><p>Otherwise, return the default value for <var>stateOrProperty</var>.</p></li>
   </ol>
 
+  <p class="note">The "default semantics" referred to here are sometimes also called "native",
+  "implicit", or "host language" semantics in <cite>ARIA</cite>. <ref spec=ARIA></p>
+
   <p>For an example of this in action, see <a href="#custom-elements-accessibility-example">the
   custom elements section</a>.</p>
 
@@ -66500,7 +66503,7 @@ customElements.define('my-checkbox', MyCheckbox);</code></pre>
     this._checked = false;
     this.addEventListener('click', this._onClick.bind(this));
 
-<mark>    this._internals.role = "checkbox";
+<mark>    this._internals.role = 'checkbox';
     this._internals.ariaChecked = false;</mark>
   }
 
@@ -68401,9 +68404,9 @@ dictionary <dfn>ValidityStateFlags</dfn> {
   <div w-nodev>
 
   <p>Each <span>custom element</span> has a <dfn>native accessibility semantics map</dfn>, which is
-  a <span>map</span>. See the <a href="#wai-aria">Requirements related to ARIA and to platform
-  accessibility APIs</a> section for information on how this impacts platform accessibility
-  APIs.</p>
+  a <span>map</span>, initially empty. See the <a href="#wai-aria">Requirements related to ARIA and
+  to platform accessibility APIs</a> section for information on how this impacts platform
+  accessibility APIs.</p>
 
   <p><code>ElementInternals</code> includes the <code>AccessibilityMixin</code> mixin. The IDL
   attributes provided by this mixin are used to manipulate the <span