[css-text-3] Add Japanese example for keep-all

Author: frivoal

css-text-3/Overview.bs

@@ -1032,6 +1032,48 @@ Line Breaking Details</h3>
       </dl>
     </div>
 
+    <div class="example" id=jp-title-break>
+      <style>
+      #jp-title-break samp {
+	font-size: 2em;
+        max-width: 9em;
+        line-height: 2;
+        padding: 0.5em 1em;
+        display: block;
+        margin: auto;
+        border: solid gray 1px;
+        background: white;
+      }
+      </style>
+      <p>Japanese is usually laid out to allow line breaks within words.
+      However, it is sometimes preferred to suppress these wrapping opportunities and to only allow wrapping at the end of certain sentence fragments.
+      This is most commonly done in very short pieces of text, such as headings, table or figure captions.
+
+      This can be achieved by marking the allowed wrapping points with <{wbr}> or U+200B ZERO WIDTH SPACE,
+      and suppressing the other ones using ''word-break: keep-all''.
+
+      For instance, the following markup can produce either of the renderings below,
+      depending on the value of the 'word-break' property:
+      <pre><code highlight=markup>
+      &lt;h1>窓ぎわの&lt;wbr>トットちゃん&lt;/h1>
+      </code></pre>
+
+      <table class=data>
+      <tr>
+        <th><code highlight=css>h1 { word-break: normal }</code>
+        <td>
+          <samp lang=ja>
+          窓ぎわの<wbr>トットちゃん
+          </samp>
+      <tr>
+        <th><pre><code highlight=css>h1 { word-break: keep-all }</code>
+        <td>
+          <samp style="word-break:keep-all" lang=ja>
+          窓ぎわの<wbr>トットちゃん
+          </samp>
+      </table>
+    </div>
+
     <p>When shaping scripts such as Arabic
       are allowed to break within words due to ''word-break/break-all''
       the characters must still be shaped