1. @DomName('WebGL2RenderingContext.stencilFuncSeparate')
  2. @DocsEditable()
  3. @Experimental()
void stencilFuncSeparate(int face, int func, int ref, int mask)

Source 

@DomName('WebGL2RenderingContext.stencilFuncSeparate')
@DocsEditable()
@Experimental() // untriaged
void stencilFuncSeparate(int face, int func, int ref, int mask) =>
    _blink.BlinkWebGL2RenderingContext.instance
        .stencilFuncSeparate_Callback_4_(this, face, func, ref, mask);