Bug 31374 Package Explorer does not show children of linked directories
org.eclipse.jdt.ui/ui/org/eclipse/jdt/ui/StandardJavaElementContentProvider.java
* Sets whether the content provider is supposed to return members
	 * when asking a compilation unit or class file for its children.
	 * 
	 * @param b if <code>true</code> then members are provided. 
	 * If <code>false</code> compilation units and class files are the
	 * leaves provided by this content provider.
	 */
	public void setProvideMembers(boolean b) {
		fProvideMembers= b;
	}
	
	/**
	 * Returns whether the provided members are from a working
	 * copy or the original compilation unit. 
	 * 
	 * @return <code>true</code> if the content provider provides
	 * working copy members; otherwise <code>false</code> is
	 * returned
	 * 
	 * @see #setProvideWorkingCopy(boolean)
	 */
	public boolean getProvideWorkingCopy() {
		return fProvideWorkingCopy;
	}
	/**
	 * Sets whether the members are provided from a shared working copy 
	 * that exists for a original compilation unit in the Java element hierarchy.
	 * 
	 * @param b if <code>true</code> members are provided from a 
	 * working copy if one exists in JDT core. If <code>false</code> the