use WeakImplHelper2 for UcbContentProviderProxyFactory

Change-Id: I211eb7f14914df88b488d48d2d6a8c204595c7e4
use WeakImplHelper2 for UcbPropertiesManager

Change-Id: I9b3c9afcf6d63f1a1e9c973c7498dcdc938f589d