Make location.search use UTF-8 unconditionally

Tests: web-platform-tests/wpt#36019.

Fixes #8308.

source

@@ -87951,8 +87951,7 @@ interface <dfn interface>Location</dfn> { // but see also <a href="#the-location
      <li><p>Set <var>copyURL</var>'s <span data-x="concept-url-query">query</span> to the empty
      string.</p></li>
 
-     <li><p><span data-x="basic url parser">Basic URL parse</span> <var>input</var>, with null, the
-     <span>relevant <code>Document</code></span>'s <span>document's character encoding</span>,
+     <li><p><span data-x="basic url parser">Basic URL parse</span> <var>input</var>,
      <var>copyURL</var> as <span data-x="basic url parser url"><i>url</i></span>, and <span>query
      state</span> as <span data-x="basic url parser state override"><i>state
      override</i></span>.</p></li>