Add a count for Suggested Articles usage.

components/ntp_snippets/content_suggestions_metrics.cc

Index: components/ntp_snippets/content_suggestions_metrics.cc
diff --git a/components/ntp_snippets/content_suggestions_metrics.cc b/components/ntp_snippets/content_suggestions_metrics.cc
index a19fef36e28515a902349a65dc13b4d65e9b6d1c..b96dfce4b74bda896fa30a47e656328bb82cf812 100644
--- a/components/ntp_snippets/content_suggestions_metrics.cc
+++ b/components/ntp_snippets/content_suggestions_metrics.cc
@@ -9,9 +9,13 @@
 
 #include "base/metrics/histogram.h"
 #include "base/metrics/histogram_macros.h"
+#include "base/metrics/user_metrics.h"
 #include "base/strings/stringprintf.h"
 #include "base/template_util.h"
 
+using base::RecordAction;
+using base::UserMetricsAction;

[Marc Treib, 2016/11/17 11:10:23]

nit: I'd prefer specifying the "base::" in the one place where it's used below.

[markusheintz_, 2016/11/17 13:48:47]

done

+
 namespace ntp_snippets {
 namespace metrics {
 
@@ -173,9 +177,11 @@ void RecordContentSuggestionsUsage() {
   size_t bucket =
       (now_exploded.hour * 60 + now_exploded.minute) / kBucketSizeMins;
 
-  UMA_HISTOGRAM_ENUMERATION(kHistogramUsageTimeLocal, bucket, kNumBuckets);
+  UMA_HISTOGRAM_ENUMERATION(kHistogramArticlesUsageTimeLocal, bucket,

[Marc Treib, 2016/11/17 11:10:23]

Bad rebase? You renamed the constant here, but not above where it's defined.

[markusheintz_, 2016/11/17 13:48:46]

Done.

+                            kNumBuckets);
 
-  LOG(ERROR) << " ****************** Zine Usage";
+  RecordAction(
+      UserMetricsAction("NewTabPage_ContentSuggestions_ArticlesUsageCount"));

[Marc Treib, 2016/11/17 11:10:23]

"Count" is implied by the fact that it's a UserAction :)
"NewTabPage_ContentSuggestions_ArticlesUsed" ?

[markusheintz_, 2016/11/17 13:48:46]

Done.

 }
 
 }  // namespace