Bug 18266 Turning off lightbulb preference doesn't turn the lights off right away
When you turn off the lightbulb preference, editors with existing lightbulbs continue to show them. Closing and reopening the editors gets rid of them.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/preferences/JavaEditorPreferencePage.java
try {
			reader= new BufferedReader(new InputStreamReader(getClass().getResourceAsStream(filename)));
			while ((line= reader.readLine()) != null) {
				buffer.append(line);
				buffer.append(separator);
			}
		} catch (IOException io) {
			JavaPlugin.log(io);
		} finally {
			if (reader != null) {
				try { reader.close(); } catch (IOException e) {}
			}
		}
		return buffer.toString();
	}
	
	private void numberFieldChanged(Text textControl) {
		String number= textControl.getText();
		IStatus status= validatePositiveNumber(number);
		if (!status.matches(IStatus.ERROR))
			fOverlayStore.setValue((String) fTextFields.get(textControl), number);
		updateStatus(status);
	}
	
	private IStatus validatePositiveNumber(String number) {
		StatusInfo status= new StatusInfo();
		if (number.length() == 0) {
			status.setError(JavaUIMessages.getString("JavaEditorPreferencePage.empty_input")); 
		} else {
			try {