Fix reshape for snapped point with Z

[lbartoletti]

Description

Reshape tool doesn't take care of snapped Z values. Indeed, QgsMapToolCapture::points() returns QgsPointXY and not map point snapped (with Z). So, we need to use snapped points from the captureCurve.

I haven't changed QVector<QgsPointXY> QgsMapToolCapture::points() to QVector<QgsPoint> QgsMapToolCapture::points() (or rename QVector<QgsPointXY> QgsMapToolCapture::pointsXY()) because it's a bugfix, I think it breaks the API. What do you think about that?

With this fix

cc @ponceta

Checklist

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[nyalldawson]

@3nids look good to you?

[3nids]

looking good!
I left a todo here qgis/qgis4.0_api#96

[lbartoletti]

@nyalldawson @3nids thanks. Can you add backports flags please?

[nyalldawson]

It's too late for that, it needs to be done before merge. You'll need to manually open the backport as a pr against 3.4.

[3nids]

@nyalldawson I'm so happy I can give you a trick for once: yes you can do it after merge :)