wireprotov2: change frame type value for command data When we dropped the dedicated command argument frame type, this left a hole in our frame type numbering. Let's start plugging that hole. The command data frame is now type value 2 instead of 3. There was limited test fallout because a) we do a good job of using the constants to refer to frame types b) not many tests are sending command data frames. Bumping the media type will be performed in a later commit, once all type value adjustment has been performed. Differential Revision: https://phab.mercurial-scm.org/D3383

--- a/tests/test-wireproto-serverreactor.py	Sat Apr 14 12:07:31 2018 -0700
+++ b/tests/test-wireproto-serverreactor.py	Sat Apr 14 12:11:24 2018 -0700
@@ -185,7 +185,7 @@
             ffs(b'1 1 stream-begin command-data 0 ignored'))
         self.assertaction(result, b'error')
         self.assertEqual(result[1], {
-            b'message': b'expected command request frame; got 3',
+            b'message': b'expected command request frame; got 2',
         })
 
     def testunexpectedcommanddatareceiving(self):