1. @DomName('WebGL2RenderingContext.getVertexAttribOffset')
  2. @DocsEditable()
  3. @Experimental()
int getVertexAttribOffset(int index, int pname)

Source 

@DomName('WebGL2RenderingContext.getVertexAttribOffset')
@DocsEditable()
@Experimental() // untriaged
int getVertexAttribOffset(int index, int pname) =>
    _blink.BlinkWebGL2RenderingContext.instance
        .getVertexAttribOffset_Callback_2_(this, index, pname);