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
IContentProposal proposal = getSelectedProposal();
			close();
			proposalAccepted(proposal);
		}
		/*
		 * Request the proposals from the proposal provider, and recompute any
		 * caches. Repopulate the popup if it is open.
		 */
		private void recomputeProposals(String filterText) {
			setProposals(getProposals(filterText));
		}
		/*
		 * In an async block, request the proposals. This is used when clients
		 * are in the middle of processing an event that affects the widget
		 * content. By using an async, we ensure that the widget content is up
		 * to date with the event.
		 */
		private void asyncRecomputeProposals(final String filterText) {
			if (isValid()) {
				control.getDisplay().asyncExec(new Runnable() {
					public void run() {
						recordCursorPosition();
						recomputeProposals(filterText);
					}
				});
			} else {
				recomputeProposals(filterText);
			}
		}
		/*