when GMSCore collects information for uploading via 'dumpsys
media.metrics', it provides the metrics service with a file descriptor
to hold the data, which is post-processed by the log collecting code
in GMScore.  This temp file lives in /data/, a place where our
restrictive policies for media.metrics doesn't allow any writing.

This relaxes the restrictions -- allowing media.metrics to
write to already open file descriptors it might be given on that
partition.

Bug: 36660639
Test: build/boot
Change-Id: Icbaa76b04ecf731014b6b1bb1283bc2951a6ae4b

Better document the reasons behind the neverallow for tcp/udp sockets.

Test: policy compiles.
Change-Id: Iee386af3be6fc7495addc9300b5628d0fe61c8e9

Introduce the add_service() macro which wraps up add/find
permissions for the source domain with a neverallow preventing
others from adding it. Only a particular domain should
add a particular service.

Use the add_service() macro to automatically add a neverallow
that prevents other domains from adding the service.

mediadrmserver was adding services labeled mediaserver_service.
Drop the add permission as it should just need the find
permission.

Additionally, the macro adds the { add find } permission which
causes some existing neverallow's to assert. Adjust those
neverallow's so "self" can always find.

Test: compile and run on hikey and emulator. No new denials were
found, and all services, where applicable, seem to be running OK.

Change-Id: Ibbd2a5304edd5f8b877bc86852b0694732be993c
Signed-off-by: William Roberts <william.c.roberts@intel.com>

reflect the change from "mediaanalytics" to "mediametrics"

Also incorporates a broader access to the service -- e.g. anyone.
This reflects that a number of metrics submissions come from application
space and not only from our controlled, trusted media related processes.
The metrics service (in another commit) checks on the source of any
incoming metrics data and limits what is allowed from unprivileged
clients.

Bug: 34615027
Test: clean build, service running and accessible
Change-Id: I657c343ea1faed536c3ee1940f1e7a178e813a42