arc: Provide more logging for network failures.

components/arc/common/auth.mojom

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// Next MinVersion: 8
+// Next MinVersion: 9
 
 module arc.mojom;
 
 // These values describe failure reason of sign-in.
 [Extensible]
 enum ArcSignInFailureReason {
   // Negative values are reserved for internal use.
   // The values are shuffled to keep the backward compatibility and don't match
   // ProvisioningResult in arc_optin_uma.h
-  // Next value: 15.
+  // Next value: 16.
   UNKNOWN_ERROR = 0,
 
   // Mojo errors:
   // MOJO_VERSION_MISMATCH: is sent when an API is not supported
   //   due to Host/Instance version mismatch.
   // MOJO_CALL_TIMEOUT: is sent when a Mojo invocation is started
   //   but not completed with time out.
   MOJO_VERSION_MISMATCH = 6,
   MOJO_CALL_TIMEOUT = 7,
 
@@ skipping 28 matching lines @@
   GMS_SERVICE_UNAVAILABLE = 2,
   GMS_BAD_AUTHENTICATION = 3,
   GMS_SIGN_IN_FAILED = 10,
   GMS_SIGN_IN_TIMEOUT = 11,
   GMS_SIGN_IN_INTERNAL_ERROR = 12,
 
   // Cloud provisioning errors.
   CLOUD_PROVISION_FLOW_FAILED = 5,
   CLOUD_PROVISION_FLOW_TIMEOUT = 13,
   CLOUD_PROVISION_FLOW_INTERNAL_ERROR = 14,
+
+  // Network connection is unavailable.
+  [MinVersion=8] NO_NETWORK_CONNECTION = 15,

[khmel, 2017/03/01 20:39:09]

 [MinVersion=8] in enum is not sufficient to uprev host version. Dummy is added
to force this.

[Yusuke Sato, 2017/03/01 20:57:10]

What happens if you send NO_NETWORK_CONNECTION to older (version=7) Chrome?

If either Chrome or the container crashes (or wildly misbehaves), adding Dummy()
seems fine, but if nothing fatal (other than NOTREACHED logs, for example)
happens, just adding the enum but not adding Dummy() might be okay.

[Luis Héctor Chávez, 2017/03/01 21:00:06]

I'm also slightly against adding the dummy function. Please file a bug in crbug/
to make the code generator take this into account (add yzshen@, but he might not
be able to take this work immediately. w.c.s. I'll get to it by end of next
week).

[khmel, 2017/03/01 21:33:06]

Personally I also consider this as minor part but for 100% correctness needed to
do that trick.
Nothing dangerous happens in worse case when Android has updated version but
Chrome not. As I tested without dummy and tricky manipulation with mojo version
"Unknown error" is shown. So I removed dummy part. Also I will be landing Chrome
first and we should never face this case.

 };
 
 // These values describe the type of the Chrome account to provision.
 [Extensible]
 enum ChromeAccountType {
   // Next value: 4
   UNKNOWN = 0,
 
   // Chrome login account type is a user account.
   USER_ACCOUNT = 1,
@@ skipping 34 matching lines @@
   // sign-in will be skipped.
   [MinVersion=6] string? enrollment_token@3;
 
   // The type of Chrome account to provision.
   ChromeAccountType account_type@1;
 
   // Whether the account is managed from Chrome OS.
   bool is_managed@2;
 };
 
-// Next Method ID: 9.
+// Next Method ID: 10.
 interface AuthHost {
   // Notifies Chrome that the sign-in is completed successfully.
   [MinVersion=2] OnSignInComplete@2();
   // Notifies Chrome that the sign-in fails to complete and provides failure
   // reason.
   [MinVersion=2] OnSignInFailed@3(ArcSignInFailureReason reason);
   // Asynchronously requests an authorization code, as well as the account
   // information.
   [MinVersion=5] RequestAccountInfo@7();
 
   // Reports metrics to Chrome to be recorded in UMA.
   [MinVersion=7] ReportMetrics@8(MetricsType metrics_type, int32 value);
 
+  // Dummy method to force update mojom version. [MinVersion=8] in enum
+  // ArcSignInFailureReasonhas has no effect.
+  [MinVersion=8] Dummy@9();

[Yusuke Sato, 2017/03/01 20:57:10]

Please move this to line 123 to lexicographically sort methods (that's the whole
point for having @N :)

[khmel, 2017/03/01 21:33:06]

Good point, however deprecated :)

+
   // Deprecated methods:
 
   // Returns an authorization code, which can be used to sign in.
   GetAuthCodeDeprecated0@0() => (string auth_code);
   // Returns an authorization code in case is_enforced is set, which can be
   // used to sign in. By default the ChromeAccountType is USER_ACCOUNT.
   [MinVersion=1] GetAuthCodeDeprecated@1() => (string auth_code,
                                                bool is_enforced);
   // Returns an authorization code and its ChromeAccountType in case
   // is_enforced is set, which can be used to sign in.
   [MinVersion=4] GetAuthCodeAndAccountTypeDeprecated@5() => (
           string auth_code, bool is_enforced, ChromeAccountType account_type);
   // Gets whether the account is managed from Chrome OS.
   [MinVersion=3] GetIsAccountManagedDeprecated@4() => (bool is_managed);
 };
 
 // Next Method ID: 2
 interface AuthInstance {
   // Establishes full-duplex communication with the host.
   Init@0(AuthHost host_ptr);
 
   // Callback from RequestAccountInfo. This cannot be a normal callback since
   // the result can sometimes take a few minutes in some cases (Kiosk mode),
   // and in other cases there is a UI that the user is shown and they can take
   // an arbitrarily long amount of time to interact with.
   // If |account_info| is null, it implies that there was an error in the
   // process.
   [MinVersion=5] OnAccountInfoReady(AccountInfo? account_info);
 };