[css-text-3] More test updates

Author: frivoal

css-text-3/Overview.bs

@@ -373,6 +373,11 @@ Text Processing</h3>
   must be ignored.
   With respect to text shaping, however, see [[#boundary-shaping]].
 
+  <wpt>
+    white-space/seg-break-transformation-018.html
+    white-space/seg-break-transformation-019.html
+  </wpt>
+
 <h2 id="transforming">
   Transforming Text</h2>
 
@@ -1399,6 +1404,8 @@ Text Processing</h3>
           <wpt>
             white-space/seg-break-transformation-016.html
             white-space/seg-break-transformation-017.html
+            white-space/seg-break-transformation-018.html
+            white-space/seg-break-transformation-019.html
           </wpt>
           <wpt pathprefix="/css/vendor-imports/mozilla/mozilla-central-reftests/text3/">
             segment-break-transformation-removable-1.html

css-text-3/test-coverage.html

@@ -95,8 +95,9 @@ <h3 id="characters-and-letters">1.4 <a href="https://drafts.csswg.org/css-text-3
 
 <h3 id="text-processing">1.5 <a href="https://drafts.csswg.org/css-text-3/#text-encoding">Text Processing</a></h3>
 
-Exhaustive coverage unrealistic, since this section is effectively a dependency on all of Unicode.
+<p>Adequate coverage.
 
+<p>Exhaustive coverage unrealistic, since this section is effectively a dependency on all of Unicode.
 Some tests nonetheless provided for sanity checking
 (such as the effect of certain control characters on Arabic shaping).