Re #7049. Remove replot that affected refresh on window resizing.

When resizing a docked waterfall plot, the background was not being
refreshed properly. The issue was traced to this call, which is not
needed in this context.
Re #7049. Add calls to replot where now required...

...after a call to updateDataCurves().
Merge remote-tracking branch 'origin/feature/7049_waterfall_resizing'