code: function jscoverage_init(w) {
    try {
      // in Safari, "import" is a syntax error
      Components.utils['import']('resource://app/modules/jscoverage.jsm');
      jscoverage_isInvertedMode = true;
      return;
    }
    catch (e) {}
  
    // check if we are in inverted mode
    if (w.opener) {
      try {
        if (w.opener.top._$jscoverage) {
          jscoverage_isInvertedMode = true;
          if (! w._$jscoverage) {
            w._$jscoverage = w.opener.top._$jscoverage;
          }
        }
        else {
          jscoverage_isInvertedMode = false;
        }
      }
      catch (e) {
        try {
          if (w.opener._$jscoverage) {
            jscoverage_isInvertedMode = true;
            if (! w._$jscoverage) {
              w._$jscoverage = w.opener._$jscoverage;
            }
          }
          else {
            jscoverage_isInvertedMode = false;
          }
        }
        catch (e2) {
          jscoverage_isInvertedMode = false;
        }
      }
    }
    else {
      jscoverage_isInvertedMode = false;
    }
  
    if (! jscoverage_isInvertedMode) {
      if (! w._$jscoverage) {
        w._$jscoverage = {};
      }
    }
  }
docs: Initializes the _$jscoverage object in a window.  This should be the first
  function called in the page.
  @param  w  this should always be the global window object