Bug 48773 [Preferences] Workbench should use ColorRegistry for color management.
Wherever possible, the workbench should use the new Color API for its colors.
bundles/org.eclipse.jface/src/org/eclipse/jface/preference/PreferenceConverter.java
* Helper method to construct a rectangle from the given string.
	 */
	private static Rectangle basicGetRectangle(String value) {
		
		
		Rectangle dr =
			new Rectangle(
				RECTANGLE_DEFAULT_DEFAULT.x,
				RECTANGLE_DEFAULT_DEFAULT.y,
				RECTANGLE_DEFAULT_DEFAULT.width,
				RECTANGLE_DEFAULT_DEFAULT.height);
		if (IPreferenceStore.STRING_DEFAULT_DEFAULT.equals(value))
			return dr;
		return StringConverter.asRectangle(value, dr);
	}
	/**
	 * Returns the current value of the color-valued preference with the
	 * given name in the given preference store.
	 * Returns the default-default value (<code>COLOR_DEFAULT_DEFAULT</code>) 
	 * if there is no preference with the given name, or if the current value 
	 * cannot be treated as a color.
	 *
	 * @param store the preference store
	 * @param name the name of the preference
	 * @return the color-valued preference
	 */
	public static RGB getColor(IPreferenceStore store, String name) {
		return basicGetColor(store.getString(name));
	}
    /**