styleguide: Make default function template arguments an allowed feature.

This patch moves default function template arguments from being
"to be discussed" to being allowed.

R=thakis@chromium.org

Review URL: https://codereview.chromium.org/1515493003

Cr-Commit-Position: refs/heads/master@{#364132}

Author: vmpstr

styleguide/c++/c++11.html

@@ -130,6 +130,16 @@ <h2 id="whitelist"><a name="core-whitelist"></a>C++11 Allowed Features</h2>
 <a href="https://groups.google.com/a/chromium.org/forum/#!topic/chromium-dev/qgU4mh_MpGA">Discussion thread</a></td>
 </tr>
 
+<tr>
+<td>Default Function Template Arguments</td>
+<td><code>template &lt;typename T = <i>type</i>&gt; <br />
+&nbsp;&nbsp;<i>type</i> <i>Function</i>(T <i>var</i>) {}</code></td>
+<td>Allow function templates, like classes, to have default arguments</td>
+<td><a href="http://stackoverflow.com/questions/2447458/default-template-arguments-for-function-templates">
+Default Template Arguments for Function Templates</a></td>
+<td><a href="https://groups.google.com/a/chromium.org/forum/#!topic/cxx/9KtaAsome-o">Discussion thread</a></td>
+</tr>
+
 <tr>
 <td>Delegated Constructors</td>
 <td><code>Class() : Class(0) {}</code><br />
@@ -613,16 +623,6 @@ <h3 id="blacklist_review"><a name="core-review"></a>C++11 Features To Be Discuss
 <td></td>
 </tr>
 
-<tr>
-<td>Default Function Template Arguments</td>
-<td><code>template &lt;typename T = <i>type</i>&gt; <br />
-&nbsp;&nbsp;<i>type</i> <i>Function</i>(T <i>var</i>) {}</code></td>
-<td>Allow function templates, like classes, to have default arguments</td>
-<td><a href="http://stackoverflow.com/questions/2447458/default-template-arguments-for-function-templates">
-Default Template Arguments for Function Templates</a></td>
-<td></td>
-</tr>
-
 <tr>
 <td>Exception Features</td>
 <td><code>noexcept</code>, <code>exception_ptr</code>,