Delete code corresponding to old UMA prefs.

chromecast/browser/metrics/cast_metrics_service_client.cc

 // 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.
 
 #include "chromecast/browser/metrics/cast_metrics_service_client.h"
 
 #include "base/command_line.h"
 #include "base/guid.h"
 #include "base/i18n/rtl.h"
 #include "base/prefs/pref_service.h"
@@ skipping 52 matching lines @@
   // backup client_id or reset to empty.
   SetMetricsClientId(client_id);
 }
 
 scoped_ptr< ::metrics::ClientInfo> CastMetricsServiceClient::LoadClientInfo() {
   scoped_ptr< ::metrics::ClientInfo> client_info(new ::metrics::ClientInfo);
 
   // kMetricsIsNewClientID would be missing if either the device was just
   // FDR'ed, or it is on pre-v1.2 build.
   if (!pref_service_->GetBoolean(prefs::kMetricsIsNewClientID)) {
-    // If the old client id exists, the device must be on pre-v1.2 build,
-    // instead of just being FDR'ed.
-    if (!pref_service_->GetString(::metrics::prefs::kMetricsOldClientID)

[gfhuang, 2015/05/29 19:54:03]

can you keep this logic and just make a local 
"const char kMetricsOldClientID[] = "user_experience_metrics.client_id" in the
top of this file.

We still don't know how many pre-v1.2 devices in the fields.

[Alexei Svitkine (slow), 2015/05/29 20:13:23]

Done.

-        .empty()) {
-      // Force old client id to be regenerated. See b/9487011.
-      client_info->client_id = base::GenerateGUID();
-      pref_service_->SetBoolean(prefs::kMetricsIsNewClientID, true);
-      return client_info.Pass();
-    }
-    // else the device was just FDR'ed, pass through.
+    client_info->client_id = base::GenerateGUID();
+    pref_service_->SetBoolean(prefs::kMetricsIsNewClientID, true);
+    return client_info.Pass();
   }
 
   const std::string client_id(GetPlatformClientID(cast_service_));
   if (!client_id.empty() && base::IsValidGUID(client_id)) {
     client_info->client_id = client_id;
     return client_info.Pass();
   } else {
     if (client_id.empty()) {
       LOG(WARNING) << "Empty client id from platform,"
                    << " assuming this is the first boot up of a new device.";
@@ skipping 180 matching lines @@
 #endif  // defined(OS_LINUX)
   metrics_service_->Stop();
 }
 
 bool CastMetricsServiceClient::IsReportingEnabled() {
   return PlatformIsReportingEnabled(cast_service_);
 }
 
 }  // namespace metrics
 }  // namespace chromecast