Add e_table_sort_info_sorting_remove().

doc/reference/evolution-util/evolution-util-sections.txt

@@ -3878,6 +3878,7 @@ ETableSortColumn
 e_table_sort_info_grouping_get_nth
 e_table_sort_info_grouping_set_nth
 e_table_sort_info_sorting_get_count
+e_table_sort_info_sorting_remove
 e_table_sort_info_sorting_truncate
 e_table_sort_info_sorting_get_nth
 e_table_sort_info_sorting_set_nth

e-util/e-table-header-item.c

@@ -1818,16 +1818,8 @@ ethi_change_sort_state (ETableHeaderItem *ethi,
 					 * This means the user has clicked twice
 					 * already, lets kill sorting of this column now.
 					 */
-					gint j;
-
-					for (j = i + 1; j < length; j++)
-						e_table_sort_info_sorting_set_nth (
-							ethi->sort_info, j - 1,
-							e_table_sort_info_sorting_get_nth (
-								ethi->sort_info, j));
-
-					e_table_sort_info_sorting_truncate (
-						ethi->sort_info, length - 1);
+					e_table_sort_info_sorting_remove (
+						ethi->sort_info, i);
 					length--;
 					i--;
 				} else {

e-util/e-table-sort-info.c

@@ -344,6 +344,25 @@ e_table_sort_info_sorting_get_count (ETableSortInfo *sort_info)
 	return sort_info->priv->sortings->len;
 }
 
+/**
+ * e_table_sort_info_sorting_remove:
+ * @sort_info: an #ETableSortInfo
+ * @n: the index of the element to remove
+ *
+ * Removes the sorting element at the given index.  The following sorting
+ * elements are moved down one place.
+ **/
+void
+e_table_sort_info_sorting_remove (ETableSortInfo *sort_info,
+                                  guint n)
+{
+	g_return_if_fail (E_IS_TABLE_SORT_INFO (sort_info));
+
+	g_array_remove_index (sort_info->priv->sortings, n);
+
+	g_signal_emit (sort_info, signals[SORT_INFO_CHANGED], 0);
+}
+
 /**
  * e_table_sort_info_sorting_truncate:
  * @sort_info: an #ETableSortInfo

e-util/e-table-sort-info.h

@@ -98,6 +98,9 @@ void		e_table_sort_info_grouping_set_nth
 
 guint		e_table_sort_info_sorting_get_count
 						(ETableSortInfo *sort_info);
+void		e_table_sort_info_sorting_remove
+						(ETableSortInfo *sort_info,
+						 guint n);
 void		e_table_sort_info_sorting_truncate
 						(ETableSortInfo *sort_info,
 						 guint length);