Merge pull request #3891 from ewilligers/text-size-adjust-non-negative

[css-size-adjust] text-size-adjust is non-negative

Author: tabatkins

css-size-adjust-1/Overview.bs

@@ -66,7 +66,7 @@ Module interactions {#placement}
 Values {#values}
 ----------------
 
-  This specification follows the <a href="https://www.w3.org/TR/CSS21/about.html#property-defs">CSS property definition conventions</a> from [[!CSS2]].
+  This specification follows the <a href="https://www.w3.org/TR/CSS21/about.html#property-defs">CSS property definition conventions</a> from [[!CSS21]].
   Value types not defined in this specification are defined in CSS Values & Units [[!CSS-VALUES-3]].
   Other CSS modules may expand the definitions of these value types.
 
@@ -151,7 +151,7 @@ Size adjustment control: the 'text-size-adjust' property {#adjustment-control}
 
   <pre class=propdef>
       Name: text-size-adjust
-      Value: auto | none | &lt;percentage&gt;
+      Value: auto | none | <<percentage>>
       Initial: auto
       Applies to: all elements
       Inherited: yes
@@ -168,7 +168,8 @@ Size adjustment control: the 'text-size-adjust' property {#adjustment-control}
       <dd>Renderers must not do size adjustment when displaying on a small device.</dd>
     <dt><dfn>&lt;percentage&gt;</dfn></dt>
       <dd>When displaying on a small device, renderers must not do size adjustment but instead the computed value of 'font-size' must be multiplied by this percentage.
-      <p class="note">Note: This means that 'text-size-adjust: 100%;' is equivalent to 'text-size-adjust: none;'.</p></dd>
+      <p class="note">Note: This means that 'text-size-adjust: 100%;' is equivalent to 'text-size-adjust: none;'.</p>
+      <p>Negative values are invalid.
   </dl>
 
   Issue: "Small device" is not well defined. We should clearly specify