Bug 125418 [Field Assist] - API - Should ContentProposalPopup be public?
In the initial release of the field assist API, the ContentProposalPopup is public. There's really no reason for this to be the case, as the popup is driven by the ContentProposalAdapter. The ContentProposalPopup should likely be made an inner type of the adapter.
bundles/org.eclipse.jface/src/org/eclipse/jface/fieldassist/ContentProposalAdapter.java
}
	/**
	 * Get the control on which the content proposal adapter is installed.
	 * 
	 * @return the control on which the proposal adapter is installed.
	 */
	public Control getControl() {
		return control;
	}
	/**
	 * Get the label provider that is used to show proposals. A default label
	 * provider will be used if one has not been set.
	 * 
	 * @return the {@link ILabelProvider} used to show proposals
	 */
	public ILabelProvider getLabelProvider() {
		if (labelProvider == null) {
			labelProvider = new LabelProvider();
		}
		return labelProvider;
	}
	/**
	 * Set the label provider that is used to show proposals.
	 * 
	 * @param labelProvider
	 *            the (@link ILabelProvider} used to show proposals.
	 */
	public void setLabelProvider(ILabelProvider labelProvider) {
		this.labelProvider = labelProvider;
	}