Obtain cached drawables using the correct Resources object

Previously we were discarding the Resources when forwarding from the
two-arg factory method to the one-arg method. This CL also updates the
documentation for ConstantState to be slightly more comprehensive.

Bug: 25688078
Change-Id: I4fbbf43f95fe792fa6f0bf9db8fd9a7cbfa51d1d
1 file changed