Fall back on the default style value if a style mapper fails #2010
Fall back on the default style value if a style mapper fails #2010

If `foo` is nil for `data(foo)` or `mapData(foo)` or non-numeric for `, then use the default style property value.  This will not cascade, like CSS.  Each property has a default value, outside of the stylesheet (as the default stylesheet is sparse).

cytoscape/cytoscape.js,cytoscape/cytoscape.js