odrefresh is the process responsible for checking and creating ART
compilation artifacts that live in the ART APEX data
directory (/data/misc/apexdata/com.android.art).
There are two types of change here:
1) enabling odrefresh to run dex2oat and write updated boot class path
and system server AOT artifacts into the ART APEX data directory.
2) enabling the zygote and assorted diagnostic tools to use the
updated AOT artifacts.
odrefresh uses two file contexts: apex_art_data_file and
apex_art_staging_data_file. When odrefresh invokes dex2oat, the
generated files have the apex_art_staging_data_file label (which allows
writing). odrefresh then moves these files from the staging area to
their installation area and gives them the apex_art_data_file label.
Bug: 160683548
Test: adb root && adb shell /apex/com.android.art/bin/odrefresh
Change-Id: I9fa290e0c9c1b7b82be4dacb9f2f8cb8c11e4895
