Send compressed histograms with system logs when sending feedback.

chrome/browser/extensions/api/feedback_private/feedback_service_chromeos.cc

Index: chrome/browser/extensions/api/feedback_private/feedback_service_chromeos.cc
diff --git a/chrome/browser/extensions/api/feedback_private/feedback_service_chromeos.cc b/chrome/browser/extensions/api/feedback_private/feedback_service_chromeos.cc
index 53afb1cd56233c476f6859420bef97b2f709cd20..b69f67cdd16edc63f166b3018ece90068f3187f0 100644
--- a/chrome/browser/extensions/api/feedback_private/feedback_service_chromeos.cc
+++ b/chrome/browser/extensions/api/feedback_private/feedback_service_chromeos.cc
@@ -6,6 +6,7 @@
 
 #include "base/callback.h"
 #include "base/memory/weak_ptr.h"
+#include "base/metrics/statistics_recorder.h"
 #include "base/values.h"
 #include "chrome/browser/chromeos/login/user_manager.h"
 #include "chrome/browser/chromeos/system_logs/scrubbed_system_logs_fetcher.h"
@@ -24,6 +25,7 @@ class FeedbackServiceImpl
   virtual std::string GetUserEmail() OVERRIDE;
   virtual void GetSystemInformation(
       const GetSystemInformationCallback& callback) OVERRIDE;
+  virtual scoped_ptr<std::string> GetHistograms() OVERRIDE;
 
  private:
   void ProcessSystemLogs(scoped_ptr<chromeos::SystemLogsResponse> sys_info);
@@ -62,6 +64,12 @@ void FeedbackServiceImpl::GetSystemInformation(
                             AsWeakPtr()));
 }
 
+scoped_ptr<std::string> FeedbackServiceImpl::GetHistograms() {

[Alexei Svitkine (slow), 2013/11/02 00:05:26]

It's pretty weird as an API to return a scoped_ptr<std::string>, it's not
commonly done.

I suggest instead using an out param here (and in related calls), i.e.:

bool FeedbackServiceImpl::GetHistograms(std::string* histograms)

Then, you don't need to alloc the string object on the heap here.

[michaelpg, 2013/11/02 17:39:09]

Replaced scoped_ptr with out param.

+  scoped_ptr<std::string> json(new std::string);
+  base::StatisticsRecorder::WriteJSON(std::string(), json.get());
+  return json.Pass();
+}
+
 void FeedbackServiceImpl::ProcessSystemLogs(
     scoped_ptr<chromeos::SystemLogsResponse> sys_info_map) {
   SystemInformationList sys_info_list;