arc: Logging ARC data removal reasons

chrome/browser/chromeos/arc/arc_optin_uma.cc

 // Copyright 2016 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.
 
 #include "chrome/browser/chromeos/arc/arc_optin_uma.h"
 
 #include "base/metrics/histogram_macros.h"
 
 namespace arc {
 
@@ skipping 36 matching lines @@
       base::TimeDelta::FromMinutes(6), 50,
       base::HistogramBase::kUmaTargetedHistogramFlag)
       ->AddTime(elapsed_time);
 }
 
 void UpdateSilentAuthCodeUMA(OptInSilentAuthCode state) {
   UMA_HISTOGRAM_ENUMERATION("Arc.OptInSilentAuthCode", static_cast<int>(state),
                             static_cast<int>(OptInSilentAuthCode::SIZE));
 }
 
+std::ostream& operator<<(std::ostream& os, const ProvisioningResult& result) {
+  switch (result) {
+    case ProvisioningResult::SUCCESS:

[Yusuke Sato, 2017/02/08 07:48:55]

How about using a macro to avoid repeating the same string twice? This seems a
bit error-prone.

[hidehiko, 2017/02/08 14:16:30]

FYI: then maybe it looks better to use something similar pattern with
https://cs.chromium.org/chromium/src/chrome/browser/chromeos/arc/arc_auth_ser...
?

[Luis Héctor Chávez, 2017/02/08 18:11:16]

sounds good. I'll also convert the one in arc_session_manager now that I'm at
it.

+      return os << "SUCCESS";
+    case ProvisioningResult::UNKNOWN_ERROR:
+      return os << "UNKNOWN_ERROR";
+    case ProvisioningResult::GMS_NETWORK_ERROR:
+      return os << "GMS_NETWORK_ERROR";
+    case ProvisioningResult::GMS_SERVICE_UNAVAILABLE:
+      return os << "GMS_SERVICE_UNAVAILABLE";
+    case ProvisioningResult::GMS_BAD_AUTHENTICATION:
+      return os << "GMS_BAD_AUTHENTICATION";
+    case ProvisioningResult::DEVICE_CHECK_IN_FAILED:
+      return os << "DEVICE_CHECK_IN_FAILED";
+    case ProvisioningResult::CLOUD_PROVISION_FLOW_FAILED:
+      return os << "CLOUD_PROVISION_FLOW_FAILED";
+    case ProvisioningResult::MOJO_VERSION_MISMATCH:
+      return os << "MOJO_VERSION_MISMATCH";
+    case ProvisioningResult::MOJO_CALL_TIMEOUT:
+      return os << "MOJO_CALL_TIMEOUT";
+    case ProvisioningResult::DEVICE_CHECK_IN_TIMEOUT:
+      return os << "DEVICE_CHECK_IN_TIMEOUT";
+    case ProvisioningResult::DEVICE_CHECK_IN_INTERNAL_ERROR:
+      return os << "DEVICE_CHECK_IN_INTERNAL_ERROR";
+    case ProvisioningResult::GMS_SIGN_IN_FAILED:
+      return os << "GMS_SIGN_IN_FAILED";
+    case ProvisioningResult::GMS_SIGN_IN_TIMEOUT:
+      return os << "GMS_SIGN_IN_TIMEOUT";
+    case ProvisioningResult::GMS_SIGN_IN_INTERNAL_ERROR:
+      return os << "GMS_SIGN_IN_INTERNAL_ERROR";
+    case ProvisioningResult::CLOUD_PROVISION_FLOW_TIMEOUT:
+      return os << "CLOUD_PROVISION_FLOW_TIMEOUT";
+    case ProvisioningResult::CLOUD_PROVISION_FLOW_INTERNAL_ERROR:
+      return os << "CLOUD_PROVISION_FLOW_INTERNAL_ERROR";
+    case ProvisioningResult::ARC_STOPPED:
+      return os << "ARC_STOPPED";
+    case ProvisioningResult::OVERALL_SIGN_IN_TIMEOUT:
+      return os << "OVERALL_SIGN_IN_TIMEOUT";
+    case ProvisioningResult::CHROME_SERVER_COMMUNICATION_ERROR:
+      return os << "CHROME_SERVER_COMMUNICATION_ERROR";
+    case ProvisioningResult::SIZE:
+      return os << "SIZE";
+  }
+
+  // Some compilers report an error even if all values of an enum-class are
+  // covered exhaustively in a switch statement.
+  NOTREACHED();
+  return os;

[Yusuke Sato, 2017/02/08 07:48:55]

os << "Invalid value " << static_cast<...>(result);

maybe slightly more useful here? (to catch uninitialized or corrupted |result|
etc.) 

[Luis Héctor Chávez, 2017/02/08 18:11:16]

Done.

+}
+
 }  // namespace arc