Add a histogram "Download.FeedbackDialogEnabled"

chrome/browser/ui/views/download/download_feedback_dialog_view.cc

Index: chrome/browser/ui/views/download/download_feedback_dialog_view.cc
diff --git a/chrome/browser/ui/views/download/download_feedback_dialog_view.cc b/chrome/browser/ui/views/download/download_feedback_dialog_view.cc
index ff716ea27fcaba2e988f329f1088fda16a083f5d..0164ec5fb6c803e211f58071e9d6d9ba1537e3dc 100644
--- a/chrome/browser/ui/views/download/download_feedback_dialog_view.cc
+++ b/chrome/browser/ui/views/download/download_feedback_dialog_view.cc
@@ -4,6 +4,7 @@
 
 #include "chrome/browser/ui/views/download/download_feedback_dialog_view.h"
 
+#include "base/metrics/histogram.h"
 #include "base/prefs/pref_service.h"
 #include "base/supports_user_data.h"
 #include "chrome/browser/profiles/profile.h"
@@ -92,6 +93,8 @@ bool DownloadFeedbackDialogView::OnButtonClicked(bool accepted) {
   DCHECK(data);
   data->set_currently_shown(false);
 
+  UMA_HISTOGRAM_BOOLEAN("Download.FeedbackDialogEnabled", accepted);
+
   callback_.Run(accepted);
   return true;
 }