With the bundle switched to Java 11, JDT compiler now complains:

The package org.w3c.dom.css is accessible from more than one module:
<unnamed>, jdk.xml.dom

if the target platform also contains javax.xml_1.3.4.v201005080400.jar
bundle.

This patch fixes the problem, removing explicit package import that
could be resolved to javax.xml_*.jar bundle also providing
org.w3c.dom.css, because the package is always provided by JDK 11.

Change-Id: Idb274273f281588ef352c67371792b4ec7297b53
Signed-off-by: Andrey Loskutov <loskutov@gmx.de>