Cumulative Sum Wrong Visualization in 0.17.1

[albertlieyingadrian]

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[Yes] I have checked the superset logs for python stacktraces and included it here as text if any
[Yes] I have reproduced the issue with at least the latest released version of superset
[Yes] I have checked the issue tracker for the same issue and I haven't found one similar

Superset version

0.17.1

Expected results

The line graph will be cumulative like in previous version (0.15.4)

Actual results

The graph is not cumulative. (The dashed line)

Steps to reproduce

1. Select any source of data
2. Select line chart
3. Go to Advanced Analytics Option
4. Set the time shift to more than 0. For example 3 days ago etc.
5. Set the rolling value to cumsum

[mxmzdlv]

I can confirm it is not working properly, version 0.19.0