Brush scale #2452

• G2 Version: v4.0.7

• Platform: MacOS, Firefox 76.0

• Mini Showcase(like screenshots):

• CodePen Link: https://codepen.io/pen/?&editable=true=https%3A%2F%2Fplotly.com%2Fjavascript%2Fline-and-scatter%2F

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  Currently, G2 brushes "snap" to data. This causes issues for column charts. Ideally, a user should be able to change the scale independent of data contained inside the scale change. I've included an example from plotly.js that demonstrates how the interaction should occur.

Related may be that brush-y doesn't seem to work on Firefox.