Stack sampling profiler: move configuration to chrome/common

chrome/common/stack_sampling_configuration.h

 // Copyright 2015 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 CHROME_BROWSER_STACK_SAMPLING_CONFIGURATION_H_
-#define CHROME_BROWSER_STACK_SAMPLING_CONFIGURATION_H_
+#ifndef CHROME_COMMON_STACK_SAMPLING_CONFIGURATION_H_
+#define CHROME_COMMON_STACK_SAMPLING_CONFIGURATION_H_
 
 #include "base/macros.h"
 #include "base/profiler/stack_sampling_profiler.h"
 
 // Chooses a configuration for the stack sampling profiler for browser process
 // startup. This must live outside of ChromeBrowserMainParts so it can be
 // friended by ChromeMetricsServiceAccessor.
 class StackSamplingConfiguration {
  public:
   StackSamplingConfiguration();
 
   // Get the stack sampling params to use for this session.
   base::StackSamplingProfiler::SamplingParams GetSamplingParams() const;
 
   // Returns true if the profiler should be started at all.
   bool IsProfilerEnabled() const;
 
-  // Register the chosen configuration as a synthetic field trial.
-  void RegisterSyntheticFieldTrial() const;
+  // Get the synthetic field trial configuration. Returns true if a synthetic
+  // field trial should be registered.
+  bool GetSyntheticFieldTrial(std::string* trial_name,
+                              std::string* group_name) const;
 
  private:
   enum ProfileConfiguration {
     PROFILE_DISABLED,
     PROFILE_CONTROL,
     PROFILE_NO_SAMPLES,  // Run the profiler thread, but don't collect profiles.
     PROFILE_5HZ,
     PROFILE_10HZ,
     PROFILE_100HZ
   };
 
   static ProfileConfiguration GenerateConfiguration();
 
   const ProfileConfiguration configuration_;
 
   DISALLOW_COPY_AND_ASSIGN(StackSamplingConfiguration);
 };
 
-#endif  // CHROME_BROWSER_STACK_SAMPLING_CONFIGURATION_H_
+#endif  // CHROME_COMMON_STACK_SAMPLING_CONFIGURATION_H_