Bug 68011 [java search] "Search the JRE System Libraries" looks like a local preference but behaves as a global one... [search]
org.eclipse.jdt.ui/ui/org/eclipse/jdt/ui/actions/FindAction.java
dialog.setElements(types);
		
		if (dialog.open() == Window.OK)
			return (IType)dialog.getFirstResult();
		else
			return RETURN_WITHOUT_BEEP;
	}
	private IType findType(IClassFile cf) {
		IType mainType;
		try {					
			mainType= cf.getType();
		} catch (JavaModelException ex) {
			if (JavaModelUtil.isExceptionToBeLogged(ex))
				ExceptionHandler.log(ex, SearchMessages.JavaElementAction_error_open_message); 
			return null;
		}
		return mainType;
	}
	
	/* 
	 * Method declared on SelectionChangedAction.
	 */
	public void run(IStructuredSelection selection) {
		IJavaElement element= getJavaElement(selection, false);
		if (element == null || !element.exists()) {
			showOperationUnavailableDialog();
			return;
		} 
		else if (element == RETURN_WITHOUT_BEEP)
			return;