Bug 147377 [Field Assist] - open proposal popup should close when there are no valid proposals left
bundles/org.eclipse.jface/src/org/eclipse/jface/fieldassist/ContentProposalAdapter.java
* Overridden to force change of colors.
		 * See https://bugs.eclipse.org/bugs/show_bug.cgi?id=136244
		 * (non-Javadoc)
		 * @see org.eclipse.jface.dialogs.PopupDialog#createContents(org.eclipse.swt.widgets.Composite)
		 */
		protected Control createContents(Composite parent) {
			Control contents = super.createContents(parent);
			changeDefaultColors(parent);
			return contents;
		}
		
		/*
		 * Set the colors of the popup.  The contents have already been created.
		 */
		private void changeDefaultColors(Control control) {
			applyForegroundColor(getShell().getDisplay().getSystemColor(
					SWT.COLOR_LIST_FOREGROUND), control);
			applyBackgroundColor(getShell().getDisplay().getSystemColor(
					SWT.COLOR_LIST_BACKGROUND), control);
		}
		/*
		 * Creates the content area for the proposal popup. This creates a table
		 * and places it inside the composite. The table will contain a list of
		 * all the proposals.
		 * 
		 * @param parent The parent composite to contain the dialog area; must
		 * not be <code>null</code>.
		 */
		protected final Control createDialogArea(final Composite parent) {