- Calculate the vertices of the shapes so that they are inscribed in the circle that has the radius of `pointRadius`
- Remove `translate()` and `rotate()` to fix the regression introduced by #5319
- Refactor `rectRounded` for better performance
Bring ctx.beginPath() before switch and replace ctx.fillRect()/ctx.strokeRect() with ctx.rect()/ctx.fill() to make it consistent with the other styles. It is also preferable that helpers.canvas.roundedRect() include ctx.closePath() at the end because CanvasRenderingContext2D.rect() closes the subpath.
Get rid of ctx.closePath() for cross, crossRot, star, line and dash because these have no closed path shape, and it should be avoided that ctx.closePath() makes a round-trip path.
Use `arcTo` instead of `quadraticCurveTo` (both methods have the same compatibility level) because it generates better results when the final rect is a circle but also when it's actually a rectangle and not a square. This change is needed by the datalabels plugin where the user can configure the `borderRadius` and thus generate circle from a rounded rectangle.
Move some of the "core" and "canvas" utils in `helpers.core.js` and `helpers.canvas.js` and introduce the new `isNullOrUndef` and `isObject` helpers. Deprecate `indexOf` and rename `drawRoundedRectangle` to `roundedRect` which now creates a simple `rect` path if radius is 0. Write missing unit tests for the moved helpers.