Reduce CPU usage of rabbit_framing_amqp_0_9_1:decode_method_fields/2decode-method-fields

This diff will generate module rabbit_framing_amqp_0_9_1 with
re-ordered clauses of function decode_method_fields/2.

After this change, basic class will be at the top of the function
clauses. That's better because for example basic.publish and basic.ack
are called far more often than for example methods of class connection,
channel or exchange.

Note that "the compiler does not rearrange clauses that match binaries."
See https://www.erlang.org/doc/efficiency_guide/functions.html#pattern-matching

Measurement taken on an Ubuntu 20.04 VM before and after this change:
1. Install latest Erlang from master (i.e. Erlang 25)
2. RABBITMQ_SERVER_ADDITIONAL_ERL_ARGS="+JPperf true +S 1" make run-broker
   (Single scheduler makes the flame graph easier to read.)
3. Run rabbitmq-perf-test without any parameters
4. sudo perf record -g -F 9999 -p <pid> -- sleep 5
   where <pid> is the output of 'os:getpid().' (in the Erlang shell).
   This samples CPU stack traces via frame pointers of
   rabbitmq-server at 9999 Hertz for 5 seconds.
5. Generate a differential flame graph as described in
   https://www.brendangregg.com/blog/2014-11-09/differential-flame-graphs.html

Before this change, stack frame rabbit_framing_amqp_0_9_1:decode_method_fields/2
was 1.57% present in all stack trackes, most of the time (> 1%) running
on the CPU, i.e. directly consuming CPU cycles.
This does not sound like a lot, but is actually quite a lot for a single
function!

The diffential flame graph depicts a single dark blue frame: function decode_method_fields
with a reduction of ~0.85%.

1 files changed, 112 insertions, 112 deletions

diff --git a/deps/rabbitmq_codegen/amqp-rabbitmq-0.9.1.json b/deps/rabbitmq_codegen/amqp-rabbitmq-0.9.1.json
index 329d63ee97..43f3cf64cd 100644
--- a/deps/rabbitmq_codegen/amqp-rabbitmq-0.9.1.json
+++ b/deps/rabbitmq_codegen/amqp-rabbitmq-0.9.1.json
@@ -99,6 +99,118 @@
 
     "classes": [
         {
+            "id": 60,
+            "methods": [{"id": 10,
+                         "arguments": [{"type": "long", "name": "prefetch-size", "default-value": 0},
+                                       {"type": "short", "name": "prefetch-count", "default-value": 0},
+                                       {"type": "bit", "name": "global", "default-value": false}],
+                         "name": "qos",
+                         "synchronous" : true},
+                        {"id": 11,
+                         "arguments": [],
+                         "name": "qos-ok"},
+                        {"id": 20,
+                         "arguments": [{"domain": "short", "name": "ticket", "default-value": 0},
+                                       {"domain": "queue-name", "name": "queue", "default-value": ""},
+                                       {"type": "shortstr", "name": "consumer-tag", "default-value": ""},
+                                       {"type": "bit", "name": "no-local", "default-value": false},
+                                       {"type": "bit", "name": "no-ack", "default-value": false},
+                                       {"type": "bit", "name": "exclusive", "default-value": false},
+                                       {"type": "bit", "name": "nowait", "default-value": false},
+                                       {"type": "table", "name": "arguments", "default-value": {}}],
+                         "name": "consume",
+                         "synchronous" : true},
+                        {"id": 21,
+                         "arguments": [{"type": "shortstr", "name": "consumer-tag"}],
+                         "name": "consume-ok"},
+                        {"id": 30,
+                         "arguments": [{"type": "shortstr", "name": "consumer-tag"},
+                                       {"type": "bit", "name": "nowait", "default-value": false}],
+                         "name": "cancel",
+                         "synchronous" : true},
+                        {"id": 31,
+                         "arguments": [{"type": "shortstr", "name": "consumer-tag"}],
+                         "name": "cancel-ok"},
+                        {"content": true,
+                         "id": 40,
+                         "arguments": [{"type": "short", "name": "ticket", "default-value": 0},
+                                       {"domain": "exchange-name", "name": "exchange", "default-value": ""},
+                                       {"type": "shortstr", "name": "routing-key", "default-value": ""},
+                                       {"type": "bit", "name": "mandatory", "default-value": false},
+                                       {"type": "bit", "name": "immediate", "default-value": false}],
+                         "name": "publish"},
+                        {"content": true,
+                         "id": 50,
+                         "arguments": [{"type": "short", "name": "reply-code"},
+                                       {"type": "shortstr", "name": "reply-text", "default-value": ""},
+                                       {"domain": "exchange-name", "name": "exchange"},
+                                       {"type": "shortstr", "name": "routing-key"}],
+                         "name": "return"},
+                        {"content": true,
+                         "id": 60,
+                         "arguments": [{"type": "shortstr", "name": "consumer-tag"},
+                                       {"type": "longlong", "name": "delivery-tag"},
+                                       {"type": "bit", "name": "redelivered", "default-value": false},
+                                       {"domain": "exchange-name", "name": "exchange"},
+                                       {"type": "shortstr", "name": "routing-key"}],
+                         "name": "deliver"},
+                        {"id": 70,
+                         "arguments": [{"type": "short", "name": "ticket", "default-value": 0},
+                                       {"domain": "queue-name", "name": "queue", "default-value": ""},
+                                       {"type": "bit", "name": "no-ack", "default-value": false}],
+                         "name": "get",
+                         "synchronous" : true},
+                        {"content": true,
+                         "id": 71,
+                         "arguments": [{"type": "longlong", "name": "delivery-tag"},
+                                       {"type": "bit", "name": "redelivered", "default-value": false},
+                                       {"domain": "exchange-name", "name": "exchange"},
+                                       {"type": "shortstr", "name": "routing-key"},
+                                       {"domain": "message-count", "name": "message-count"}],
+                         "name": "get-ok"},
+                        {"id": 72,
+                         "arguments": [{"type": "shortstr", "name": "cluster-id", "default-value": ""}],
+                         "name": "get-empty"},
+                        {"id": 80,
+                         "arguments": [{"type": "longlong", "name": "delivery-tag", "default-value": 0},
+                                       {"type": "bit", "name": "multiple", "default-value": false}],
+                         "name": "ack"},
+                        {"id": 90,
+                         "arguments": [{"type": "longlong", "name": "delivery-tag"},
+                                       {"type": "bit", "name": "requeue", "default-value": true}],
+                         "name": "reject"},
+                        {"id": 100,
+                         "arguments": [{"type": "bit", "name": "requeue", "default-value": false}],
+                         "name": "recover-async"},
+                        {"id": 110,
+                         "arguments": [{"type": "bit", "name": "requeue", "default-value": false}],
+                         "name": "recover",
+                         "synchronous" : true},
+                        {"id": 111,
+                         "arguments": [],
+                         "name": "recover-ok"},
+                        {"id": 120,
+                         "arguments": [{"type": "longlong", "name": "delivery-tag", "default-value": 0},
+                                       {"type": "bit", "name": "multiple", "default-value": false},
+                                       {"type": "bit", "name": "requeue", "default-value": true}],
+                         "name": "nack"}],
+            "name": "basic",
+            "properties": [{"type": "shortstr", "name": "content-type"},
+                           {"type": "shortstr", "name": "content-encoding"},
+                           {"type": "table", "name": "headers"},
+                           {"type": "octet", "name": "delivery-mode"},
+                           {"type": "octet", "name": "priority"},
+                           {"type": "shortstr", "name": "correlation-id"},
+                           {"type": "shortstr", "name": "reply-to"},
+                           {"type": "shortstr", "name": "expiration"},
+                           {"type": "shortstr", "name": "message-id"},
+                           {"type": "timestamp", "name": "timestamp"},
+                           {"type": "shortstr", "name": "type"},
+                           {"type": "shortstr", "name": "user-id"},
+                           {"type": "shortstr", "name": "app-id"},
+                           {"type": "shortstr", "name": "cluster-id"}]
+        },
+        {
             "id": 10,
             "methods": [{"id": 10,
                          "arguments": [{"type": "octet", "name": "version-major", "default-value": 0},
@@ -331,118 +443,6 @@
             "name": "queue"
         },
         {
-            "id": 60,
-            "methods": [{"id": 10,
-                         "arguments": [{"type": "long", "name": "prefetch-size", "default-value": 0},
-                                       {"type": "short", "name": "prefetch-count", "default-value": 0},
-                                       {"type": "bit", "name": "global", "default-value": false}],
-                         "name": "qos",
-                         "synchronous" : true},
-                        {"id": 11,
-                         "arguments": [],
-                         "name": "qos-ok"},
-                        {"id": 20,
-                         "arguments": [{"domain": "short", "name": "ticket", "default-value": 0},
-                                       {"domain": "queue-name", "name": "queue", "default-value": ""},
-                                       {"type": "shortstr", "name": "consumer-tag", "default-value": ""},
-                                       {"type": "bit", "name": "no-local", "default-value": false},
-                                       {"type": "bit", "name": "no-ack", "default-value": false},
-                                       {"type": "bit", "name": "exclusive", "default-value": false},
-                                       {"type": "bit", "name": "nowait", "default-value": false},
-                                       {"type": "table", "name": "arguments", "default-value": {}}],
-                         "name": "consume",
-                         "synchronous" : true},
-                        {"id": 21,
-                         "arguments": [{"type": "shortstr", "name": "consumer-tag"}],
-                         "name": "consume-ok"},
-                        {"id": 30,
-                         "arguments": [{"type": "shortstr", "name": "consumer-tag"},
-                                       {"type": "bit", "name": "nowait", "default-value": false}],
-                         "name": "cancel",
-                         "synchronous" : true},
-                        {"id": 31,
-                         "arguments": [{"type": "shortstr", "name": "consumer-tag"}],
-                         "name": "cancel-ok"},
-                        {"content": true,
-                         "id": 40,
-                         "arguments": [{"type": "short", "name": "ticket", "default-value": 0},
-                                       {"domain": "exchange-name", "name": "exchange", "default-value": ""},
-                                       {"type": "shortstr", "name": "routing-key", "default-value": ""},
-                                       {"type": "bit", "name": "mandatory", "default-value": false},
-                                       {"type": "bit", "name": "immediate", "default-value": false}],
-                         "name": "publish"},
-                        {"content": true,
-                         "id": 50,
-                         "arguments": [{"type": "short", "name": "reply-code"},
-                                       {"type": "shortstr", "name": "reply-text", "default-value": ""},
-                                       {"domain": "exchange-name", "name": "exchange"},
-                                       {"type": "shortstr", "name": "routing-key"}],
-                         "name": "return"},
-                        {"content": true,
-                         "id": 60,
-                         "arguments": [{"type": "shortstr", "name": "consumer-tag"},
-                                       {"type": "longlong", "name": "delivery-tag"},
-                                       {"type": "bit", "name": "redelivered", "default-value": false},
-                                       {"domain": "exchange-name", "name": "exchange"},
-                                       {"type": "shortstr", "name": "routing-key"}],
-                         "name": "deliver"},
-                        {"id": 70,
-                         "arguments": [{"type": "short", "name": "ticket", "default-value": 0},
-                                       {"domain": "queue-name", "name": "queue", "default-value": ""},
-                                       {"type": "bit", "name": "no-ack", "default-value": false}],
-                         "name": "get",
-                         "synchronous" : true},
-                        {"content": true,
-                         "id": 71,
-                         "arguments": [{"type": "longlong", "name": "delivery-tag"},
-                                       {"type": "bit", "name": "redelivered", "default-value": false},
-                                       {"domain": "exchange-name", "name": "exchange"},
-                                       {"type": "shortstr", "name": "routing-key"},
-                                       {"domain": "message-count", "name": "message-count"}],
-                         "name": "get-ok"},
-                        {"id": 72,
-                         "arguments": [{"type": "shortstr", "name": "cluster-id", "default-value": ""}],
-                         "name": "get-empty"},
-                        {"id": 80,
-                         "arguments": [{"type": "longlong", "name": "delivery-tag", "default-value": 0},
-                                       {"type": "bit", "name": "multiple", "default-value": false}],
-                         "name": "ack"},
-                        {"id": 90,
-                         "arguments": [{"type": "longlong", "name": "delivery-tag"},
-                                       {"type": "bit", "name": "requeue", "default-value": true}],
-                         "name": "reject"},
-                        {"id": 100,
-                         "arguments": [{"type": "bit", "name": "requeue", "default-value": false}],
-                         "name": "recover-async"},
-                        {"id": 110,
-                         "arguments": [{"type": "bit", "name": "requeue", "default-value": false}],
-                         "name": "recover",
-                         "synchronous" : true},
-                        {"id": 111,
-                         "arguments": [],
-                         "name": "recover-ok"},
-                        {"id": 120,
-                         "arguments": [{"type": "longlong", "name": "delivery-tag", "default-value": 0},
-                                       {"type": "bit", "name": "multiple", "default-value": false},
-                                       {"type": "bit", "name": "requeue", "default-value": true}],
-                         "name": "nack"}],
-            "name": "basic",
-            "properties": [{"type": "shortstr", "name": "content-type"},
-                           {"type": "shortstr", "name": "content-encoding"},
-                           {"type": "table", "name": "headers"},
-                           {"type": "octet", "name": "delivery-mode"},
-                           {"type": "octet", "name": "priority"},
-                           {"type": "shortstr", "name": "correlation-id"},
-                           {"type": "shortstr", "name": "reply-to"},
-                           {"type": "shortstr", "name": "expiration"},
-                           {"type": "shortstr", "name": "message-id"},
-                           {"type": "timestamp", "name": "timestamp"},
-                           {"type": "shortstr", "name": "type"},
-                           {"type": "shortstr", "name": "user-id"},
-                           {"type": "shortstr", "name": "app-id"},
-                           {"type": "shortstr", "name": "cluster-id"}]
-        },
-        {
             "id": 90,
             "methods": [{"id": 10,
                          "arguments": [],