Stokhos: Remove calls to deprecated Kokkos::View methods

[mhoemmen]

Kokkos will soon deprecate the following Kokkos::View methods:

1. ptr_on_device(): replace with data()
2. dimension(N) (for N = 0, 1, 2, ..., 7): replace with extent(N)
3. dimension_N() (for N = 0, 1, 2, ..., 7): replace with extent(N)
4. is_contiguous(): replace with span_is_contiguous()
5. capacity(): replace with span()

Sierra is already seeing build errors with its Trilinos integration build, since Sierra doesn't define KOKKOS_ENABLE_DEPRECATED_CODE. If that macro is not defined, code that uses the above methods will not build.

@trilinos/stokhos @etphipp

[etphipp]

Can this be closed now?

[mhoemmen]

@etphipp yes; thanks! Please refer to #2735 for further Kokkos promotion issues.