Bug 43488 [typing] BadPositionCategoryException in LinkedPositionManager
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/text/link/contentassist/ContentAssistant2.java
reset(showStyle);
			else
				start(showStyle);
		}
				
		protected void showAssist(final int showStyle) {
			Control control= fViewer.getTextWidget();
			Display d= control.getDisplay();
			if (d != null) {
				try {
					d.syncExec(new Runnable() {
						public void run() {
							if (showStyle == SHOW_PROPOSALS)
								fProposalPopup.showProposals(true);
							else if (showStyle == SHOW_CONTEXT_INFO)
								fContextInfoPopup.showContextProposals(true);
						}
					});
				} catch (SWTError e) {
				}
			}
		}
	}
	
	/**
	 * The laypout manager layouts the various
	 * windows associated with the content assistant based on the
	 * settings of the content assistant.
	 */
	class LayoutManager implements Listener {