Merge branch 'maint'

* maint:
  git-gui: Ensure consistent usage of mergetool.keepBackup
  git-gui: fix use of undeclared variable diff_empty_count

git-gui.sh

@@ -722,7 +722,7 @@ proc apply_config {} {
 
 set default_config(branch.autosetupmerge) true
 set default_config(merge.tool) {}
-set default_config(merge.keepbackup) true
+set default_config(mergetool.keepbackup) true
 set default_config(merge.diffstat) true
 set default_config(merge.summary) false
 set default_config(merge.verbosity) 2
@@ -1131,6 +1131,7 @@ set current_diff_path {}
 set is_3way_diff 0
 set is_conflict_diff 0
 set selected_commit_type new
+set diff_empty_count 0
 
 set nullid "0000000000000000000000000000000000000000"
 set nullid2 "0000000000000000000000000000000000000001"

lib/mergetool.tcl

@@ -382,7 +382,7 @@ proc merge_tool_finish {fd} {
 		delete_temp_files $mtool_tmpfiles
 		ui_status [mc "Merge tool failed."]
 	} else {
-		if {[is_config_true merge.keepbackup]} {
+		if {[is_config_true mergetool.keepbackup]} {
 			file rename -force -- $backup "$mtool_target.orig"
 		}