Move more endpoints to singleton scope and remove providers

Ia2ac8cfcc moved some REST endpoints to singleton scope, but missed
to remove providers from these endpoints, where they get injected.

When a singleton injects another singleton, this is only an overhead
to inject it as a provider to singleton and not directly.

Change-Id: I6d6f361cc2c46440845ef13ccacb8ec4f28c9b36
Merge "Move more endpoints to singleton scope and remove providers"