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diff --git a/chromium/chrome/common/stack_sampling_configuration.h b/chromium/chrome/common/stack_sampling_configuration.h
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+++ b/chromium/chrome/common/stack_sampling_configuration.h
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+// 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_COMMON_STACK_SAMPLING_CONFIGURATION_H_
+#define CHROME_COMMON_STACK_SAMPLING_CONFIGURATION_H_
+
+#include <string>
+
+#include "base/callback.h"
+#include "base/macros.h"
+#include "base/profiler/stack_sampling_profiler.h"
+
+namespace base {
+class CommandLine;
+}  // namespace base
+
+// StackSamplingConfiguration chooses a configuration for the enable state of
+// the stack sampling profiler across all processes. This configuration is
+// determined once at browser process startup. Configurations for child
+// processes are communicated via command line arguments.
+class StackSamplingConfiguration {
+ public:
+  StackSamplingConfiguration();
+
+  // Get the stack sampling params to use for this process.
+  base::StackSamplingProfiler::SamplingParams
+      GetSamplingParamsForCurrentProcess() const;
+
+  // Returns true if the profiler should be started for the current process.
+  bool IsProfilerEnabledForCurrentProcess() const;
+
+  // Get the synthetic field trial configuration. Returns true if a synthetic
+  // field trial should be registered. This should only be called from the
+  // browser process. When run at startup, the profiler must use a synthetic
+  // field trial since it runs before the metrics field trials are initialized.
+  bool GetSyntheticFieldTrial(std::string* trial_name,
+                              std::string* group_name) const;
+
+  // Add a command line switch that instructs the child process to run the
+  // profiler. This should only be called from the browser process.
+  void AppendCommandLineSwitchForChildProcess(
+      const std::string& process_type,
+      base::CommandLine* command_line) const;
+
+  // Returns the StackSamplingConfiguration for the process.
+  static StackSamplingConfiguration* Get();
+
+ private:
+  // Configuration to use for this Chrome instance.
+  enum ProfileConfiguration {
+    // Chrome-wide configurations set in the browser process.
+    PROFILE_DISABLED,
+    PROFILE_CONTROL,
+    PROFILE_ENABLED,
+
+    // Configuration set in the child processes, which receive their enable
+    // state on the command line from the browser process.
+    PROFILE_FROM_COMMAND_LINE
+  };
+
+  // Configuration variations, along with weights to use when randomly choosing
+  // one of a set of variations.
+  struct Variation {
+    ProfileConfiguration config;
+    int weight;
+  };
+
+  // Randomly chooses a configuration from the weighted variations. Weights are
+  // expected to sum to 100 as a sanity check.
+  static ProfileConfiguration ChooseConfiguration(
+      const std::vector<Variation>& variations);
+
+  // Generates sampling profiler configurations for all processes.
+  static ProfileConfiguration GenerateConfiguration();
+
+  // NOTE: all state in this class must be const and initialized at construction
+  // time to ensure thread-safe access post-construction.
+
+  // In the browser process this represents the configuration to use across all
+  // Chrome processes. In the child processes it is always
+  // PROFILE_FROM_COMMAND_LINE.
+  const ProfileConfiguration configuration_;
+
+  DISALLOW_COPY_AND_ASSIGN(StackSamplingConfiguration);
+};
+
+#endif  // CHROME_COMMON_STACK_SAMPLING_CONFIGURATION_H_