logd: object layer format statistics

(cherry pick from commit 758058ffd8820df71c27db7675c50a90a5fa02b4)

Simplify table generation by placing the line and header formatting
into each type's (UID, PID, TID) object. Switch to const return
values for the ownership passing functions (*ToName() functions
and methods). Use longer variable names to reduce confusion.

Switch from LINES To NUM for pruned column as that more accurately
reflects what is dropped since one entry can contain several lines.

Bug: 22855208
Change-Id: Ib110dce98a68cf5f844eb30f8a192a1f691eeba2
5 files changed