The polls were wrong about Btexit and Trump.
Not true actually.
The polls prior to brexit bounced between remain and leave leads - the reason why people were surprised was because many assumed their would be a late swing to remain.
The polls in the US presidential election (which are predictions of overall vote share) were pretty well spot on, predicting a couple of point lead for Clinton in the nation vote share. Trump won because he picked up the key states he needed - the French presidential run off will be a straight winner on national vote share.
However the key point is that in brexit and US presidential elections the polls were showing the two sides pretty close to neck and neck. In the French run off the polls are showing either Macron or Fillon beating LePen by about 65% to 35% - that's a massive gap, nothing like the neck and neck reported by the polls in the other 2 cases.