Wrong context for onresize/onresized callback

[netil]

Description

onresize and onresized options callback, must executed on the chart instance context,
but they're ran on ChartInternal context instead of the Chart.

Steps to check or reproduce

{
  onresize: function() {
    console.log(this);  // this should be Chart
  },
  onresized: function() {
    console.log(this);  // this should be Chart
  }
}