code: function()
      {
          if (WebInspector.CodeMirrorTextEditor._whitespaceStyleInjected || !WebInspector.settings.showWhitespacesInEditor.get())
              return;
          WebInspector.CodeMirrorTextEditor._whitespaceStyleInjected = true;
          const classBase = ".show-whitespaces .CodeMirror .cm-whitespace-";
          const spaceChar = "·";
          var spaceChars = "";
          var rules = "";
          for (var i = 1; i <= WebInspector.CodeMirrorTextEditor.MaximumNumberOfWhitespacesPerSingleSpan; ++i) {
              spaceChars += spaceChar;
              var rule = classBase + i + "::before { content: '" + spaceChars + "';}\n";
              rules += rule;
          }
          var style = createElement("style");
          style.textContent = rules;
          document.head.appendChild(style);
      }
docs: // FIXME: remove this suppression.
  @suppressGlobalPropertiesCheck