Push API: Refactor and fix unsubscribe API

content/public/common/push_messaging_status.h

 // Copyright 2014 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.
 
 #ifndef CONTENT_PUBLIC_COMMON_PUSH_MESSAGING_STATUS_H_
 #define CONTENT_PUBLIC_COMMON_PUSH_MESSAGING_STATUS_H_
 
 namespace content {
 
 // Push registration success/error codes for internal use & reporting in UMA.
@@ skipping 47 matching lines @@
 
   // NOTE: Do not renumber these as that would confuse interpretation of
   // previously logged data. When making changes, also update the enum list
   // in tools/metrics/histograms/histograms.xml to keep it in sync, and
   // update PUSH_REGISTRATION_STATUS_LAST below.
 
   PUSH_REGISTRATION_STATUS_LAST =
       PUSH_REGISTRATION_STATUS_MANIFEST_EMPTY_OR_MISSING
 };
 
+// Push unregistration reason for reporting in UMA.

[Mark P, 2016/09/30 22:39:03]

Please add standard warning label here (yes, I see you have something similar
below too), something like
These values are written to logs.  New enum values can be added, but existing
enums must never be renumbered or deleted and reused.

[johnme, 2016/09/30 23:10:41]

Done (added "Enum values can be added, but must never be renumbered or deleted
and reused." to each of the enums in this class, as they're all used for UMA).

+enum PushUnregistrationReason {
+  // Should never happen.
+  PUSH_UNREGISTRATION_REASON_UNKNOWN = 0,
+
+  // Unregistering because the website called the unsubscribe API.
+  PUSH_UNREGISTRATION_REASON_JAVASCRIPT_API = 1,
+
+  // Unregistering because the user manually revoked permission.
+  PUSH_UNREGISTRATION_REASON_PERMISSION_REVOKED = 2,
+
+  // Automatic - incoming message's app id was unknown.
+  PUSH_UNREGISTRATION_REASON_DELIVERY_UNKNOWN_APP_ID = 3,
+
+  // Automatic - incoming message's origin no longer has permission.
+  PUSH_UNREGISTRATION_REASON_DELIVERY_PERMISSION_DENIED = 4,
+
+  // Automatic - incoming message's service worker was not found.
+  PUSH_UNREGISTRATION_REASON_DELIVERY_NO_SERVICE_WORKER = 5,
+
+  // NOTE: Do not renumber these as that would confuse interpretation of
+  // previously logged data. When making changes, also update the enum list
+  // in tools/metrics/histograms/histograms.xml to keep it in sync, and
+  // update PUSH_UNREGISTRATION_REASON_LAST below.
+
+  PUSH_UNREGISTRATION_REASON_LAST =
+      PUSH_UNREGISTRATION_REASON_DELIVERY_NO_SERVICE_WORKER
+};
+
 // Push unregistration success/error codes for internal use & reporting in UMA.
 enum PushUnregistrationStatus {
   // The unregistration was successful.
   PUSH_UNREGISTRATION_STATUS_SUCCESS_UNREGISTERED = 0,
 
   // Unregistration was unnecessary, as the registration was not found.
   PUSH_UNREGISTRATION_STATUS_SUCCESS_WAS_NOT_REGISTERED = 1,
 
   // The unregistration did not happen because of a network error, but will be
   // retried until it succeeds.
@@ skipping 110 matching lines @@
       PUSH_USER_VISIBLE_STATUS_REQUIRED_BUT_NOT_SHOWN_GRACE_EXCEEDED
 };
 
 const char* PushRegistrationStatusToString(PushRegistrationStatus status);
 
 const char* PushUnregistrationStatusToString(PushUnregistrationStatus status);
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_COMMON_PUSH_MESSAGING_STATUS_H_