doc/go1.14: document that unparsable URL in net/url/Error is now quoted

Fixes golang#37614
Updates golang#36878

doc/go1.14.html

@@ -759,6 +759,19 @@ <h3 id="minor_library_changes">Minor changes to the library</h3>
   </dd>
 </dl><!-- net/textproto -->
 
+<dl id="net/url"><dt><a href="/pkg/net/url/">net/url</a></dt>
+  <dd>
+    <p><!-- CL 185117 -->
+      When parsing of an URL fails 
+      (e.g. by <a href="/pkg/net/url/#Parse"><code>Parse</code></a> 
+      or <a href="/pkg/net/url/#ParseRequestURI"><code>ParseRequestURI</code></a>),
+      the resulting <a href="/pkg/net/url/#Error.Error"><code>Error</code></a> message 
+      will now quote the unparsable URL
+      for clearer structure and consistency with other parsing errors.
+    </p>
+  </dd>
+</dl><!-- net/url -->
+
 <dl id="os/signal"><dt><a href="/pkg/os/signal/">os/signal</a></dt>
   <dd>
     <p><!-- CL 187739 -->