move saveRangeInitial call in graphWasEmpty block:
move saveRangeInitial call in graphWasEmpty block:

- so that restyle calls that update that purge gd.calcdata
  don't update the 'initial' axis ranges.
- save initial range even if gd._context settings are such
  that it won't get used (in case gd._context changes during the
  plot life cycle).

plotly/plotly.js,plotly/plotly.js,etpinard/plotly.js,asolagmbh/plotly.js,etpinard/plotly.js,aburato/plotly.js,plotly/plotly.js,aburato/plotly.js,iongroup/plotly.js,asolagmbh/plotly.js,asolagmbh/plotly.js,etpinard/plotly.js,plotly/plotly.js,iongroup/plotly.js,iongroup/plotly.js