Allow composd to create odrefresh staging directory

composd in responsible to prepare the staging directory for odrefresh
(in the VM) to write the output to. Temporary output should be put in a
staged directory with a temporary apex_art_staging_data_file context.
When a compilation is finished, the files can then be moved to the final
directory with the final context.

Bug: 205750213
Test: No denials

Change-Id: I9444470b31518242c1bb84fc755819d459d21d68
2 files changed