Migrate system/core/base to system/libbase.

Add Symlink to ensure hardcoded references do not break build.
BUG: 148941208
test: TH

Change-Id: Ia2b69de1af6e07be2aab3ba4fe1493de80269c40
Merged-In: I1134f1e9e968b9273748e2483bea8d25e5c9e994
82 files changed