1. @DomName('SVGPatternElement.hasExtension')
  2. @DocsEditable()
bool hasExtension(String extension)

Source 

@DomName('SVGPatternElement.hasExtension')
@DocsEditable()
bool hasExtension(String extension) => _blink.BlinkSVGPatternElement.instance
    .hasExtension_Callback_1_(this, extension);