Bug 72615 [Viewers] Need and ITableFontProvider
We released an ITabelColorProvider for M2 - we should have a corresponding ITableFontProvider
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/AbstractTreeViewer.java
* 
     * @param element
     *           the element
     * @return <code>true</code> if the node is expanded, and <code>false</code>
     *         if collapsed
     */
    public boolean getExpandedState(Object element) {
        Assert.isNotNull(element);
        Widget item = findItem(element);
        if (item instanceof Item)
            return getExpanded((Item) item);
        return false;
    }
    /**
     * Returns the number of child items of the given SWT control.
     * 
     * @param control
     *           the control
     * @return the number of children
     */
    protected abstract int getItemCount(Control control);
    /**
     * Returns the number of child items of the given SWT item.
     * 
     * @param item
     *           the item
     * @return the number of children
     */
    protected abstract int getItemCount(Item item);
    /**