Refactoring vCard importer/exporter.

Rename ImportVCardService to VCardService and make it responsible for all the import/export works.
The service itself asks ImportProcessor/ExportProcessor to handle each request.
This implementation seems much more easier to be tested than the previous ones.

Bug: 2733143

Change-Id: I7b7d391e4ba294f74c8bbcdfb053368b61b498ca
12 files changed