Reset metrics if cellular uploads logic should be applied.

chrome/browser/metrics/chrome_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 "chrome/browser/metrics/chrome_metrics_service_client.h"
 
 #include <vector>
 
 #include "base/bind.h"
 #include "base/callback.h"
@@ skipping 83 matching lines @@
 bool IsCellularLogicEnabled() {
   if (variations::GetVariationParamValue("UMA_EnableCellularLogUpload",
                                          "Enabled") != "true") {
     return false;
   }
 
   return net::NetworkChangeNotifier::IsConnectionCellular(
       net::NetworkChangeNotifier::GetConnectionType());
 }
 
-}  // namespace
+// Checks whether it is the first time that cellular uploads logic should be
+// enabled based on whether the the preference for that logic is initialized.
+// This should happen only once as the used preference will be initialized
+// afterwards in |UmaSessionStats.java|.
+bool ShouldClearSavedMetrics() {
+#if !defined(OS_ANDROID)
+  return false;
+#endif
+  PrefService* local_state = g_browser_process->local_state();
+  return !local_state->HasPrefPath(prefs::kMetricsReportingEnabled) &&
+         variations::GetVariationParamValue("UMA_EnableCellularLogUpload",
+                                            "Enabled") == "true";
+}
+
+}  // anonymous namespace

[Alexei Svitkine (slow), 2015/05/13 14:36:02]

Nit: No need to say "anonymous", just "  // namespace" is fine.

[gayane -on leave until 09-2017, 2015/05/13 14:46:02]

Done.

+
 
 ChromeMetricsServiceClient::ChromeMetricsServiceClient(
     metrics::MetricsStateManager* state_manager)
     : metrics_state_manager_(state_manager),
       chromeos_metrics_provider_(nullptr),
       waiting_for_collect_final_metrics_step_(false),
       num_async_histogram_fetches_in_progress_(0),
       profiler_metrics_provider_(nullptr),
 #if defined(ENABLE_PLUGINS)
       plugin_metrics_provider_(nullptr),
@@ skipping 157 matching lines @@
 void ChromeMetricsServiceClient::LogPluginLoadingError(
     const base::FilePath& plugin_path) {
 #if defined(ENABLE_PLUGINS)
   plugin_metrics_provider_->LogPluginLoadingError(plugin_path);
 #else
   NOTREACHED();
 #endif  // defined(ENABLE_PLUGINS)
 }
 
 void ChromeMetricsServiceClient::Initialize() {
+  // Clear metrics reports if it is the first time cellular upload logic should
+  // apply to avoid sudden bulk uploads. It needs to be done before initializing
+  // metrics service so that metrics log manager is initialized correctly.
+  if (ShouldClearSavedMetrics()) {
+    local_state->ClearPref(metrics::prefs::kMetricsInitialLogs);
+    local_state->ClearPref(metrics::prefs::kMetricsOngoingLogs);
+  }
+
   metrics_service_.reset(new metrics::MetricsService(
       metrics_state_manager_, this, g_browser_process->local_state()));
 
   // Register metrics providers.
 #if defined(ENABLE_EXTENSIONS)
   metrics_service_->RegisterMetricsProvider(
       scoped_ptr<metrics::MetricsProvider>(
           new ExtensionsMetricsProvider(metrics_state_manager_)));
 #endif
   metrics_service_->RegisterMetricsProvider(
@@ skipping 64 matching lines @@
       new SigninStatusMetricsProviderChromeOS;
   metrics_service_->RegisterMetricsProvider(
       scoped_ptr<metrics::MetricsProvider>(signin_metrics_provider_cros));
 #endif  // defined(OS_CHROMEOS)
 
 #if !defined(OS_CHROMEOS) && !defined(OS_IOS)
   metrics_service_->RegisterMetricsProvider(
       scoped_ptr<metrics::MetricsProvider>(
           SigninStatusMetricsProvider::CreateInstance()));
 #endif  // !defined(OS_CHROMEOS) && !defined(OS_IOS)
+
+  // Clear stability metrics if it is the first time cellular upload logic
+  // should apply to avoid sudden bulk uploads. It needs to be done after all
+  // providers are registered.
+  if (ShouldClearSavedMetrics())
+    metrics_service_->ClearSavedStabilityMetrics();
 }
 
 void ChromeMetricsServiceClient::OnInitTaskGotHardwareClass() {
   const base::Closure got_plugin_info_callback =
       base::Bind(&ChromeMetricsServiceClient::OnInitTaskGotPluginInfo,
                  weak_ptr_factory_.GetWeakPtr());
 
 #if defined(ENABLE_PLUGINS)
   plugin_metrics_provider_->GetPluginInformation(got_plugin_info_callback);
 #else
@@ skipping 149 matching lines @@
     case content::NOTIFICATION_LOAD_START:
     case content::NOTIFICATION_RENDERER_PROCESS_CLOSED:
     case content::NOTIFICATION_RENDER_WIDGET_HOST_HANG:
       metrics_service_->OnApplicationNotIdle();
       break;
 
     default:
       NOTREACHED();
   }
 }