Merge branch 'jk/color-variable-fixes'

Some places in the code confused a variable that is *not* a boolean
to enable color but is an enum that records what the user requested
to do about color.  A couple of bugs of this sort have been fixed,
while the code has been cleaned up to prevent similar bugs in the
future.

* jk/color-variable-fixes:
  config: store want_color() result in a separate bool
  add-interactive: retain colorbool values longer
  color: return bool from want_color()
  color: use git_colorbool enum type to store colorbools
  pretty: use format_commit_context.auto_color as colorbool
  diff: stop passing ecbdata->use_color as boolean
  diff: pass o->use_color directly to fill_metainfo()
  diff: don't use diff_options.use_color as a strict bool
  diff: simplify color_moved check when flushing
  grep: don't treat grep_opt.color as a strict bool
  color: return enum from git_config_colorbool()
  color: use GIT_COLOR_* instead of numeric constants

log-tree.c

@@ -57,7 +57,7 @@ static const char *color_decorate_slots[] = {
 	[DECORATION_GRAFTED]	= "grafted",
 };
 
-static const char *decorate_get_color(int decorate_use_color, enum decoration_type ix)
+static const char *decorate_get_color(enum git_colorbool decorate_use_color, enum decoration_type ix)
 {
 	if (want_color(decorate_use_color))
 		return decoration_colors[ix];
@@ -341,7 +341,7 @@ static void show_name(struct strbuf *sb, const struct name_decoration *decoratio
  */
 void format_decorations(struct strbuf *sb,
 			const struct commit *commit,
-			int use_color,
+			enum git_colorbool use_color,
 			const struct decoration_options *opts)
 {
 	const struct name_decoration *decoration;