Adding client side field trial for sampling on non-stable channels.

chrome/browser/chrome_browser_field_trials.cc

 // Copyright (c) 2012 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/chrome_browser_field_trials.h"
 
 #include <string>
 
 #include "base/command_line.h"
 #include "base/feature_list.h"
 #include "base/files/file_util.h"
 #include "base/metrics/field_trial.h"
 #include "base/metrics/histogram_base.h"
 #include "base/metrics/histogram_macros.h"
 #include "base/metrics/persistent_histogram_allocator.h"
 #include "base/path_service.h"
 #include "base/strings/string_util.h"
 #include "base/time/time.h"
 #include "build/build_config.h"
 #include "chrome/browser/metrics/chrome_metrics_service_client.h"
 #include "chrome/browser/metrics/chrome_metrics_services_manager_client.h"
 #include "chrome/browser/tracing/background_tracing_field_trial.h"
 #include "chrome/common/channel_info.h"
 #include "chrome/common/chrome_paths.h"
 #include "chrome/common/chrome_switches.h"
 #include "components/metrics/metrics_pref_names.h"
 #include "components/variations/variations_associated_data.h"
-#include "components/version_info/version_info.h"
 
 #if defined(OS_ANDROID)
 #include "chrome/browser/chrome_browser_field_trials_mobile.h"
 #else
 #include "chrome/browser/chrome_browser_field_trials_desktop.h"
 #endif
 
 namespace {
 
 // Check for feature enabling the use of persistent histogram storage and
@@ skipping 81 matching lines @@
                                          base::FeatureList* feature_list) {
 #if defined(OS_WIN) || defined(OS_ANDROID)
   // Only create the fallback trial if there isn't already a variations seed
   // being applied. This should occur during first run when first-run variations
   // isn't supported. It's assumed that, if there is a seed, then it either
   // contains the relavent study, or is intentionally omitted, so no fallback is
   // needed.
   if (has_seed)
     return;
 
-  // Sampling is only supported on Stable.
-  if (chrome::GetChannel() != version_info::Channel::STABLE)
-    return;
-
-  ChromeMetricsServicesManagerClient::CreateFallbackSamplingTrial(feature_list);
+  ChromeMetricsServicesManagerClient::CreateFallbackSamplingTrial(
+      chrome::GetChannel(), feature_list);
 #endif  // defined(OS_WIN) || defined(OS_ANDROID)
 }
 
 }  // namespace
 
 ChromeBrowserFieldTrials::ChromeBrowserFieldTrials(
     const base::CommandLine& parsed_command_line)
     : parsed_command_line_(parsed_command_line) {
 }
 
@@ skipping 15 matching lines @@
     bool has_seed,
     base::FeatureList* feature_list) {
   CreateFallbackSamplingTrialIfNeeded(has_seed, feature_list);
 }
 
 void ChromeBrowserFieldTrials::InstantiateDynamicTrials() {
   // Persistent histograms must be enabled as soon as possible.
   InstantiatePersistentHistograms();
   tracing::SetupBackgroundTracingFieldTrial();
 }