CSS issues after #745

[jperedadnr]

After #745, importing a control that uses its own user agent stylesheet fails, because Modena.css overwrites it.

Expected Behavior

Importing ControlsFX Rating control should show:

Current Behavior

Importing ControlsFX Rating control shows:

Steps to Reproduce

Add ControlsFX to the custom library, open a new FXML file, add an AnchorPane and a Rating control. The size is wrong, because button's padding defaults to modena's padding:

instead of 16 (from its rating.css)

Rating uses:

    @Override public String getUserAgentStylesheet() {
        return getUserAgentStylesheet(Rating.class, "rating.css");
    }

Your Environment

Screenshots

[jperedadnr]

Actually, there was an underlying bug in Scene Builder, and this bug was already happening before #745, but after #720, with other themes.

For instance, High contrast Black and White + Rating, :

The problem: before #745, modena.bss was used in EditorPlatform Theme.MODENA. That was converted to css with Deprecation::getThemeTextStylesheet, but

try {
            return new URL(textCssUrlStr);
        } catch (MalformedURLException ex) {
            // should never happen
            return null;
        }

was always returning null, since this exception was totally ignored:

java.net.MalformedURLException: no protocol: com/sun/javafx/scene/control/skin/modena/modena.css
	at java.base/java.net.URL.<init>(URL.java:772)
	at java.base/java.net.URL.<init>(URL.java:654)
	at java.base/java.net.URL.<init>(URL.java:590)
	at com.gluonhq.scenebuilder.kit@24.0.0-SNAPSHOT/com.oracle.javafx.scenebuilder.kit.util.Deprecation.getThemeTextStylesheet(Deprecation.java:189)

Therefore, the default Modena theme wasn't adding any style classes at all, while other modena themes that imported directly modena.css were, and the user agent stylesheets from custom controls were also overwritten.