PerfProvider: Run a randomly selected perf command

chrome/browser/metrics/perf/perf_provider_chromeos.h

Index: chrome/browser/metrics/perf/perf_provider_chromeos.h
diff --git a/chrome/browser/metrics/perf/perf_provider_chromeos.h b/chrome/browser/metrics/perf/perf_provider_chromeos.h
index 081f16dc124dca107ed92a954bb0417700472547..359301a2151e5e9e768aad1c61c753aecb65a8e0 100644
--- a/chrome/browser/metrics/perf/perf_provider_chromeos.h
+++ b/chrome/browser/metrics/perf/perf_provider_chromeos.h
@@ -13,6 +13,8 @@
 #include "base/threading/non_thread_safe.h"
 #include "base/time/time.h"
 #include "base/timer/timer.h"
+#include "chrome/browser/metrics/perf/cpu_identity.h"
+#include "chrome/browser/metrics/perf/random_selector.h"
 #include "chrome/browser/sessions/session_restore.h"
 #include "chromeos/dbus/power_manager_client.h"
 #include "chromeos/login/login_state.h"
@@ -195,6 +197,9 @@ class PerfProvider : public base::NonThreadSafe,
   // Parameters controlling how profiles are collected.
   CollectionParams collection_params_;
 
+  // Set of commands to choose from.
+  RandomSelector command_selector_;
+
   // Vector of SampledProfile protobufs containing perf profiles.
   std::vector<SampledProfile> cached_perf_data_;
 
@@ -227,6 +232,15 @@ class PerfProvider : public base::NonThreadSafe,
   DISALLOW_COPY_AND_ASSIGN(PerfProvider);
 };
 
+namespace internal {
+
+// Exposed for unit testing.
+
+const std::vector<RandomSelector::WeightAndValue> GetDefaultCommandsForCpu(

[Alexei Svitkine (slow), 2015/10/13 17:31:19]

Nit: No need for const on the return value

[dhsharp, 2015/10/13 23:36:22]

Done.

+    const CPUIdentity& cpuid);
+
+}  // namespace internal
+
 }  // namespace metrics
 
 #endif  // CHROME_BROWSER_METRICS_PERF_PERF_PROVIDER_CHROMEOS_H_