code: function getStylingContext(index) {
      var stylingContext = load(index);
      if (!Array.isArray(stylingContext)) {
          var lElement = stylingContext;
          var tNode = lElement.tNode;
          ngDevMode &&
              assertDefined(tNode.stylingTemplate, 'getStylingContext() called before elementStyling()');
          stylingContext = viewData[index + HEADER_OFFSET] =
              allocStylingContext(lElement, tNode.stylingTemplate);
      }
      return stylingContext;
  }
docs: Retrieve the `StylingContext` at a given index.
  
  This method lazily creates the `StylingContext`. This is because in most cases
  we have styling without any bindings. Creating `StylingContext` eagerly would mean that
  every style declaration such as `<div style="color: red">` would result `StyleContext`
  which would create unnecessary memory pressure.
  
  @param index Index of the style allocation. See: `elementStyling`.