update method
Update a specific coordinate in a part.
Parameters
coord: New Coordinates value.index: Index of the coordinate to update.part: Optional part index (if omitted, part 0 is used).
Implementation
void update(final Coordinates coord, final int index, {final int part = 0}) {
objectMethod(
_pointerId,
'Marker',
'update',
args: <String, Object>{'coord': coord, 'index': index, 'part': part},
);
}