Make it easy to override preferred-branch test

* Makefile.in (preferred-branch-is-current):
Rename from emacs-25-branch-is-current.  All uses changed.
(PREFERRED_BRANCH): New macro.

1 files changed, 5 insertions, 4 deletions

diff --git a/Makefile.in b/Makefile.in
index 7b8328c2195..31a073b6749 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -1092,7 +1092,7 @@ bootstrap: bootstrap-clean
         $(MAKE) all
 
 .PHONY: ChangeLog change-history change-history-commit change-history-nocommit
-.PHONY: emacs-25-branch-is-current unchanged-history-files
+.PHONY: preferred-branch-is-current unchanged-history-files
 
 CHANGELOG = ChangeLog
 emacslog = build-aux/gitlog-to-emacslog
@@ -1109,8 +1109,9 @@ ChangeLog:
           ./$(emacslog) -o $(CHANGELOG) -n $(CHANGELOG_HISTORY_INDEX_MAX)
 
 # Check that we are in a good state for changing history.
-emacs-25-branch-is-current:
-        git branch | grep -q '^\* emacs-25$$'
+PREFERRED_BRANCH = master
+preferred-branch-is-current:
+        git branch | grep -q '^\* $(PREFERRED_BRANCH)$$'
 unchanged-history-files:
         x=$$(git diff-files --name-only $(CHANGELOG_N) $(emacslog)) && \
           test -z "$$x"
@@ -1120,7 +1121,7 @@ new_commit_regexp = ^commit [0123456789abcdef]* (inclusive)
 
 # Copy newer commit messages to the start of the ChangeLog history file,
 # and consider them to be older.
-change-history-nocommit: emacs-25-branch-is-current unchanged-history-files
+change-history-nocommit: preferred-branch-is-current unchanged-history-files
         -rm -f ChangeLog.tmp
         $(MAKE) ChangeLog CHANGELOG=ChangeLog.tmp
         sed '/^This file records repository revisions/,$$d' \