Bug 128425 [Help] Help button should not show up in dialogs without help context ID
I20060216-2000 The Help button should not show up in dialogs without help context ID. Examples in this build are the 'Source > Clean Up...' wizard or 'plugin context menu > PDE Tools > Organize Manifests...'.
bundles/org.eclipse.jface/src/org/eclipse/jface/dialogs/TrayDialog.java
layout.horizontalSpacing = 0;
		return layout;
	}
	
	/**
	 * Returns the tray currently shown in the dialog, or <code>null</code>
	 * if there is no tray.
	 * 
	 * @return the dialog's current tray, or <code>null</code> if there is none
	 */
	public DialogTray getTray() {
		return tray;
	}
	
	/*
	 * Called when the help control is invoked. This emulates the keyboard
	 * context help behavior (e.g. F1 on Windows). It traverses the widget
	 * tree upward until it finds a widget that has a help listener on it,
	 * then invokes a help event on that widget.
	 */
	private void helpPressed() {
    	if (getShell() != null) {
	    	Control c = getShell().getDisplay().getFocusControl();
	    	while (c != null) {
	    		if (c.isListening(SWT.Help)) {
	    			c.notifyListeners(SWT.Help, new Event());
	    			break;
	    		}
	    		c = c.getParent();
	    	}