multi: add reset closure to kvdb.Update

Similarly as with kvdb.View this commits adds a reset closure to the
kvdb.Update call in order to be able to reset external state if the
underlying db backend needs to retry the transaction.

channeldb/meta_test.go

@@ -209,7 +209,7 @@ func TestMigrationWithPanic(t *testing.T) {
 			}
 
 			return bucket.Put(keyPrefix, beforeMigration)
-		})
+		}, func() {})
 		if err != nil {
 			t.Fatalf("unable to insert: %v", err)
 		}
@@ -251,7 +251,7 @@ func TestMigrationWithPanic(t *testing.T) {
 			}
 
 			return nil
-		})
+		}, func() {})
 		if err != nil {
 			t.Fatal(err)
 		}
@@ -283,7 +283,7 @@ func TestMigrationWithFatal(t *testing.T) {
 			}
 
 			return bucket.Put(keyPrefix, beforeMigration)
-		})
+		}, func() {})
 		if err != nil {
 			t.Fatalf("unable to insert pre migration key: %v", err)
 		}
@@ -326,7 +326,7 @@ func TestMigrationWithFatal(t *testing.T) {
 			}
 
 			return nil
-		})
+		}, func() {})
 		if err != nil {
 			t.Fatal(err)
 		}
@@ -359,7 +359,7 @@ func TestMigrationWithoutErrors(t *testing.T) {
 			}
 
 			return bucket.Put(keyPrefix, beforeMigration)
-		})
+		}, func() {})
 		if err != nil {
 			t.Fatalf("unable to update db pre migration: %v", err)
 		}
@@ -401,7 +401,7 @@ func TestMigrationWithoutErrors(t *testing.T) {
 			}
 
 			return nil
-		})
+		}, func() {})
 		if err != nil {
 			t.Fatal(err)
 		}
@@ -448,7 +448,7 @@ func TestMigrationReversion(t *testing.T) {
 		}
 
 		return putMeta(newMeta, tx)
-	})
+	}, func() {})
 
 	// Close the database. Even if we succeeded, our next step is to reopen.
 	cdb.Close()