Make channels instantiated with a user-provided number recoverable

Closes #670

(cherry picked from commit a7bd239)

Author: michaelklishin

src/main/java/com/rabbitmq/client/impl/recovery/AutorecoveringConnection.java

@@ -176,7 +176,13 @@ public Channel createChannel() throws IOException {
      */
     @Override
     public Channel createChannel(int channelNumber) throws IOException {
-        return delegate.createChannel(channelNumber);
+        RecoveryAwareChannelN ch = (RecoveryAwareChannelN) delegate.createChannel(channelNumber);
+        // No Sonar: the channel could be null
+        if (ch == null) { //NOSONAR
+            return null;
+        } else {
+            return this.wrapChannel(ch);
+        }
     }
 
     /**

src/test/java/com/rabbitmq/client/test/functional/ConnectionRecovery.java

@@ -281,6 +281,22 @@ public void handleUnblocked() throws IOException {
         expectChannelRecovery(ch2);
     }
 
+    @Test public void channelRecoveryWithUserProvidedChannelIDs() throws IOException, InterruptedException {
+        int n1 = 11;
+        Channel ch1 = connection.createChannel(n1);
+        int n2 = 22;
+        Channel ch2 = connection.createChannel(n2);
+
+        assertThat(ch1.isOpen()).isTrue();
+        assertThat(ch2.isOpen()).isTrue();
+        closeAndWaitForRecovery();
+        expectChannelRecovery(ch1);
+        expectChannelRecovery(ch2);
+
+        assertThat(ch1.getChannelNumber()).isEqualTo(n1);
+        assertThat(ch2.getChannelNumber()).isEqualTo(n2);
+    }
+
     @Test public void returnListenerRecovery() throws IOException, InterruptedException {
         final CountDownLatch latch = new CountDownLatch(1);
         channel.addReturnListener(new ReturnListener() {