Bug 256656 [FieldAssist] cancel auto activation of proposal popup when caret moved
bundles/org.eclipse.jface/src/org/eclipse/jface/fieldassist/ContentProposalAdapter.java
* Request the proposals from the proposal provider, and recompute any
		 * caches. Repopulate the popup if it is open.
		 */
		private void recomputeProposals(String filterText) {
			IContentProposal[] allProposals = getProposals();
			
			
			
			if (allProposals.length == 0) {
				proposals = allProposals;
				close();
			} else {
				
				setProposals(filterProposals(allProposals, 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);
					}
				});