metropolis/pkg/logtree: move logtree protobuf definition to logtree pkg

Before this change we had the LogEntry message inside the metropolis
common proto file. This splits it out into the logtree package to make
it standalone in a future change.

Change-Id: Idb26a829d6174efa946a6c4ce0f1b984cb2f18a2
Reviewed-on: https://review.monogon.dev/c/monogon/+/3080
Tested-by: Jenkins CI
Reviewed-by: Serge Bazanski <serge@monogon.tech>
diff --git a/metropolis/pkg/logtree/leveled.go b/metropolis/pkg/logtree/leveled.go
index 5c57222..0facbb1 100644
--- a/metropolis/pkg/logtree/leveled.go
+++ b/metropolis/pkg/logtree/leveled.go
@@ -19,7 +19,7 @@
 import (
 	"fmt"
 
-	cpb "source.monogon.dev/metropolis/proto/common"
+	lpb "source.monogon.dev/metropolis/pkg/logtree/proto"
 )
 
 // LeveledLogger is a generic interface for glog-style logging. There are four
@@ -144,32 +144,32 @@
 	}
 }
 
-func SeverityFromProto(s cpb.LeveledLogSeverity) (Severity, error) {
+func SeverityFromProto(s lpb.LeveledLogSeverity) (Severity, error) {
 	switch s {
-	case cpb.LeveledLogSeverity_INFO:
+	case lpb.LeveledLogSeverity_INFO:
 		return INFO, nil
-	case cpb.LeveledLogSeverity_WARNING:
+	case lpb.LeveledLogSeverity_WARNING:
 		return WARNING, nil
-	case cpb.LeveledLogSeverity_ERROR:
+	case lpb.LeveledLogSeverity_ERROR:
 		return ERROR, nil
-	case cpb.LeveledLogSeverity_FATAL:
+	case lpb.LeveledLogSeverity_FATAL:
 		return FATAL, nil
 	default:
 		return "", fmt.Errorf("unknown severity value %d", s)
 	}
 }
 
-func (s Severity) ToProto() cpb.LeveledLogSeverity {
+func (s Severity) ToProto() lpb.LeveledLogSeverity {
 	switch s {
 	case INFO:
-		return cpb.LeveledLogSeverity_INFO
+		return lpb.LeveledLogSeverity_INFO
 	case WARNING:
-		return cpb.LeveledLogSeverity_WARNING
+		return lpb.LeveledLogSeverity_WARNING
 	case ERROR:
-		return cpb.LeveledLogSeverity_ERROR
+		return lpb.LeveledLogSeverity_ERROR
 	case FATAL:
-		return cpb.LeveledLogSeverity_FATAL
+		return lpb.LeveledLogSeverity_FATAL
 	default:
-		return cpb.LeveledLogSeverity_INVALID
+		return lpb.LeveledLogSeverity_INVALID
 	}
 }