Fix package handling in Resources_Delegate.getIdentifier

Resources.getIdentifier always expect to be able to construct a fully
qualified name for the resource, with package + id + name. A missing or
invalid package should make it return 0 for resource not found.

Bug: 115618017
Test: RenderTests.testResourcesGetIdentifier updated
Change-Id: I4d6253fdb58f2046394b6e50f5f58d4bc787c6ae
(cherry picked from commit afceda29e54090d13f5d68565b3d52046842f354)