api/server/router/network: remove unused Backend.FindNetwork

This function was used by the postNetworkConnect() handler, but is handled
by the backend itself, starting with d63a5a1ff593f14957f3e0a9678633e8237defc9.
Since that commit, this function was no longer used, so we can remove it.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

api/server/router/network/backend.go

@@ -6,13 +6,11 @@ import (
 	"github.com/docker/docker/api/types"
 	"github.com/docker/docker/api/types/filters"
 	"github.com/docker/docker/api/types/network"
-	"github.com/docker/docker/libnetwork"
 )
 
 // Backend is all the methods that need to be implemented
 // to provide network specific functionality.
 type Backend interface {
-	FindNetwork(idName string) (*libnetwork.Network, error)
 	GetNetworks(filters.Args, types.NetworkListConfig) ([]types.NetworkResource, error)
 	CreateNetwork(nc types.NetworkCreateRequest) (*types.NetworkCreateResponse, error)
 	ConnectContainerToNetwork(containerName, networkName string, endpointConfig *network.EndpointSettings) error