In order to make sure these APIs work properly, we have to flush style before
building the path to make sure the d property is up-to-date.
1. isPointInFill()
2. isPointInStroke()
3. getTotalLength()
4. getPointAtLength()
5. getPathSegAtLength() (note: Legacy API, only Gecko and WebKit support.)
Differential Revision: https://phabricator.services.mozilla.com/D133434