[CrOS MultiDevice] Update DCHECK() in AuthenticatedChannelImpl.

This DCHECK() asserted that a SecureChannel status change could only be
AUTHENTICATED => DISCONNECTING, AUTHENTICATED => DISCONNECTED, or
DISCONNECTING => DISCONNECTED.

However, AUTHENTICATING => AUTHENTICATED is also a valid status change,
so I added that to part of the DCHECK().

This issue was discovered when attempting to enable DCHECK()s by
default in accordance with the recent e-mail announcements.

Change-Id: Ia5126b70e25245f49d04939ae2e1e0bc0ea9315a
Reviewed-on: https://chromium-review.googlesource.com/c/1352996Reviewed-by: Ryan Hansberry <hansberry@chromium.org>
Commit-Queue: Kyle Horimoto <khorimoto@chromium.org>
Cr-Commit-Position: refs/heads/master@{#611928}

chromeos/services/secure_channel/authenticated_channel_impl.cc

@@ -97,11 +97,14 @@ void AuthenticatedChannelImpl::OnSecureChannelStatusChanged(
     const cryptauth::SecureChannel::Status& new_status) {
   DCHECK_EQ(secure_channel_.get(), secure_channel);
 
-  // The only expected status changes are AUTHENTICATED => DISCONNECTING,
-  // AUTHENTICATED => DISCONNECTED, and DISCONNECTING => DISCONNECTED.
-  DCHECK(old_status == cryptauth::SecureChannel::Status::AUTHENTICATED ||
+  // The only expected status changes are AUTHENTICATING => AUTHENTICATED,
+  // AUTHENTICATED => DISCONNECTING, AUTHENTICATED => DISCONNECTED, and
+  // DISCONNECTING => DISCONNECTED.
+  DCHECK(old_status == cryptauth::SecureChannel::Status::AUTHENTICATING ||
+         old_status == cryptauth::SecureChannel::Status::AUTHENTICATED ||
          old_status == cryptauth::SecureChannel::Status::DISCONNECTING);
-  DCHECK(new_status == cryptauth::SecureChannel::Status::DISCONNECTING ||
+  DCHECK(new_status == cryptauth::SecureChannel::Status::AUTHENTICATED ||
+         new_status == cryptauth::SecureChannel::Status::DISCONNECTING ||
          new_status == cryptauth::SecureChannel::Status::DISCONNECTED);
 
   if (new_status == cryptauth::SecureChannel::Status::DISCONNECTED)