[css-text-decor-3] Add the spelling-error and grammar-error decorations

Author: frivoal

css-text-decor-3/Overview.bs

@@ -18,6 +18,7 @@ Abstract: This module contains the features of CSS relating to text decoration,
 At Risk: The 'text-decoration-skip' property.
 At Risk: The line positioning rules.
 At Risk: The ability to place both emphasis marks and ruby on the same base text.
+At Risk: The ''spelling-error'' and ''grammar-error'' values of the 'text-decoration-line' property.
 Link Defaults: css-color-3 (property) color
 Use <i> Autolinks: yes
 </pre>
@@ -179,7 +180,7 @@ Text Decoration Lines: the 'text-decoration-line' property</h3>
 
   <pre class="propdef">
   Name: text-decoration-line
-  Value: none | [ underline || overline || line-through || blink ]
+  Value: none | [ underline || overline || line-through || blink ] | spelling-error | grammar-error
   Initial: none
   Inherited: no (but see prose, above)
   </pre>
@@ -203,8 +204,27 @@ Text Decoration Lines: the 'text-decoration-line' property</h3>
         Conforming user agents may simply not blink the text.
         Note that not blinking the text is one technique to satisfy <a href="https://www.w3.org/TR/UAAG/guidelines.html#tech-on-off-blinking-text">checkpoint 3.3 of WAI-UAAG</a>.
         This value is <strong>deprecated</strong> in favor of Animations [[CSS3-ANIMATIONS]].
+    <dt><dfn value for="text-tecoration-line">spelling-error</dfn>
+      <dd>This values indicates the type of text decoration used by the User Agent
+          to highlight spelling mistakes.
+	  It's appearance is UA defined.
+	  <span class=note>It is often rendered as a red wavy underline.</span>
+    <dt><dfn value for="text-decoration-line">grammar-error</dfn>
+      <dd>This values indicates the type of text decoration used by the User Agent
+          to highlight grammar mistakes.
+	  It's appearance is UA defined.
+	  <span class=note>It is often rendered as a green wavy underline.</span>
   </dl>
 
+    When the value of 'text-decoration-line' is either ''spelling-error'' or ''grammar-error'',
+    the UA may disregard the values of the other <a>sub-properties</a> of 'text-decoration',
+    as well as those of other properties affecting the appearance of the text-decoration such as 'text-underline-position'.
+    To the extent that honoring these properties would be meaningful and practical given the UA's chosen rendering,
+    the UA should apply them, but is not required to.
+
+    Note: The ''spelling-error'' and ''grammar-error'' values are at risk.
+
+
 <h3 id="text-decoration-color-property">
 Text Decoration Color: the 'text-decoration-color' property</h3>
 
@@ -974,4 +994,5 @@ Changes</h2>
         (<a href="https://drafts.csswg.org/css-text-decor-3/issues-cr-2013#issue-11">Issue 11</a>, <a href="https://drafts.csswg.org/css-text-decor-3/issues-cr-2013#issue-18">Issue 18</a>, <a href="https://drafts.csswg.org/css-text-decor-3/issues-cr-2013#issue-19">Issue 19</a>)
     <li>Added rule to apply ''font-variant-east-asian/ruby'' to emphasis marks' font.
         (<a href="https://drafts.csswg.org/css-text-decor-3/issues-cr-2013#issue-13">Issue 13</a>)
+    <li>Added the ''spelling-error'' and ''grammar-error' values to 'text-decoration' (marked at risk).
   </ul>