slog: rename openScopes to openGroups

Removing the last occurrences of "scope" in the code.

Change-Id: Iefed72d97b99c948b46eb5523fb85bdc8ff16dbd
Reviewed-on: https://go-review.googlesource.com/c/exp/+/443071
Run-TryBot: Jonathan Amsterdam <jba@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Alan Donovan <adonovan@google.com>
diff --git a/slog/handler.go b/slog/handler.go
index 88f15dc..0a1afff 100644
--- a/slog/handler.go
+++ b/slog/handler.go
@@ -186,7 +186,7 @@
 	if len(h2.preformattedAttrs) > 0 {
 		state.sep = h.attrSep()
 	}
-	state.openScopes()
+	state.openGroups()
 	for _, a := range as {
 		state.appendAttr(a)
 	}
@@ -280,7 +280,7 @@
 	s.prefix = buffer.New()
 	defer s.prefix.Free()
 	s.prefix.WriteString(s.h.groupPrefix)
-	s.openScopes()
+	s.openGroups()
 	r.Attrs(func(a Attr) {
 		s.appendAttr(a)
 	})
@@ -312,7 +312,7 @@
 	prefix *buffer.Buffer // for text: key prefix
 }
 
-func (s *handleState) openScopes() {
+func (s *handleState) openGroups() {
 	for _, n := range s.h.groups[s.h.nOpenGroups:] {
 		s.openGroup(n)
 	}