9f236037a2
1, add a new field in storage metadata proto, for each container, there is a local override file. 2, update write api to expose the api to map a writable file given the specific path. the cannonical api will require a storage metadata proto, and then find the right file path and map it. 3, minor update to make the proto lib cc_library instead of cc_library_static Bug: b/312444587 Test: atest -c Change-Id: Iaf0aff44c1ca3ad4bffc5e06bb99bb276b9069c5