Restore the original style properties of all matches.

        This method effectively removes all visible traces of
        the match highlighting.

def clearHighlighting(self):
        """
        Restore the original style properties of all matches.

        This method effectively removes all visible traces of
        the match highlighting.
        """
        SCI = self.qteWidget
        self.qteWidget.SCISetStylingEx(0, 0, self.styleOrig)

        # Clear out the match set and reset the match index.
        self.selMatchIdx = 1
        self.matchList = []