Previously, when setting startFill/endFill, the display was inverted
comparing to the configuration.
The marker was filled when set to false, not filled when set to true.
When not set, the marker was filled, which is the expected default.
The issue came from a wrong condition to manage the default value and
was reproduced with the Markers Story.
In addition to the code fix, update the Markers.stories.js to fix style
configurations
- use number instead of string for markers size
- use boolean instead of number for start/end fill
3fff754cd6