patch 7.4.1257

Problem:    Channel test fails in some configurations.
Solution:   Add check for the +channel feature.

src/testdir/test_channel.vim

@@ -1,7 +1,11 @@
 " Test for channel functions.
 scriptencoding utf-8
 
-" This requires the Python command to run the test server.
+if !has('channel')
+  finish
+endif
+
+" This test requires the Python command to run the test server.
 " This most likely only works on Unix and Windows console.
 if has('unix')
   " We also need the pkill command to make sure the server can be stopped.

src/version.c

@@ -742,6 +742,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1257,
 /**/
     1256,
 /**/