[PowerProfiler] Power Profiler service should detect the sampling rate from the data provider.

content/browser/power_profiler/power_data_provider.h

Index: content/browser/power_profiler/power_data_provider.h
diff --git a/content/browser/power_profiler/power_data_provider.h b/content/browser/power_profiler/power_data_provider.h
index f6c043811f016479cfacc53ff05150fe25e116ec..55c3cd8c4db2a7141625a1788934d9210a03a7cf 100644
--- a/content/browser/power_profiler/power_data_provider.h
+++ b/content/browser/power_profiler/power_data_provider.h
@@ -7,6 +7,7 @@
 
 #include <vector>
 
+#include "base/basictypes.h"

[sky, 2014/06/04 15:31:48]

Why do you need to add this? If it's to get base::TimeDelta you should forward
declare it.

[vivekg, 2014/06/04 16:49:31]

Done.

 #include "base/memory/scoped_ptr.h"
 #include "content/browser/power_profiler/power_event.h"
 
@@ -24,6 +25,9 @@ class PowerDataProvider {
 
   // Returns a vector of power events, one per type, for the types it supports.
   virtual PowerEventVector GetData() = 0;
+
+  // Returns sampling rate at which the provider can operate.
+  virtual base::TimeDelta GetSamplingRate() = 0;
 };
 
 }  // namespace content