Bug 5571 JAR Packager: Reveal first checked project
If the list of projects in the JAR Packager is long it is possible that the shown projects are not checked even though there are checked projects (due to current selection). ==> reveal the first checked project.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/jarpackager/CheckboxTreeAndListGroup.java
protected void treeItemChecked(Object treeElement, boolean state) {
		
		setTreeChecked(treeElement, state);
		Object parent= fTreeContentProvider.getParent(treeElement);
		if (parent == null)
			return;
		 
		if (state)
			grayCheckHierarchy(parent);
		else
			ungrayCheckHierarchy(parent);
		updateHierarchy(treeElement);
	}
	/**
	 *	Logically un-gray-check all ancestors of treeItem iff appropriate.
	 */
	protected void ungrayCheckHierarchy(Object treeElement) {
		if (!determineShouldBeAtLeastGrayChecked(treeElement))
			fCheckedStateStore.remove(treeElement);
		Object parent= fTreeContentProvider.getParent(treeElement);
		if (parent != null)
			ungrayCheckHierarchy(parent);
	}
	/**
	 *	Sets the checked state of self and all ancestors appropriately
	 */
	protected void updateHierarchy(Object treeElement) {
		boolean whiteChecked= determineShouldBeWhiteChecked(treeElement);
		boolean shouldBeAtLeastGray= determineShouldBeAtLeastGrayChecked(treeElement);
		fTreeViewer.setChecked(treeElement, shouldBeAtLeastGray);