Update diskstats to break out code & data.

This updates both the text-based diskstats and the proto-based diskstats
to both have both an aggregated and line-itemed view of app sizes.
Formerly, the code and data sizes were rolled up into the same category
and now they are separated.

Bug: 63908720
Test: FrameworksServicesTest passes
Merged-In: I1434327ffde6ad1f31243218c5201a80f9725a63
(cherry picked from commit b6cc8381)
(cherry picked from commit 41a5ae86)

Change-Id: I0d21ecc0ded5d715e3b5a478e78de2ba1f7e9ec2