veyron/runtimes/google/security: Export a single PrivateID factory method.

This change unexports NewChainPrivateID and NewTreePrivateID and provides a single
NewPrivateID. This prevents clients of this library from worrying about which
implementation to choose and if we ever decide that we want to default to the
Tree implementation, then we have a single place to change (and fix up
any breaking tests).

Change-Id: I500d2ccd69ea8cc4e8571bf02face4814caf2d9d
8 files changed
tree: 9ebcc796f98819f7a907987854cccbd2d63eeb7d
  1. examples/
  2. lib/
  3. runtimes/
  4. services/
  5. tools/