Redoing Issue 36073011: Allowing file:/// in Instant Extended's Most Visited links.

chrome/browser/ui/webui/ntp/ntp_user_data_logger.cc

Index: chrome/browser/ui/webui/ntp/ntp_user_data_logger.cc
diff --git a/chrome/browser/ui/webui/ntp/ntp_user_data_logger.cc b/chrome/browser/ui/webui/ntp/ntp_user_data_logger.cc
index 27d1cdf651ba5b6d6dd6c9a8ca92afb0de9c2561..088fcf5f4ec887ec795b9f5c2ba06871cacbff0d 100644
--- a/chrome/browser/ui/webui/ntp/ntp_user_data_logger.cc
+++ b/chrome/browser/ui/webui/ntp/ntp_user_data_logger.cc
@@ -13,6 +13,7 @@
 #include "chrome/common/url_constants.h"
 #include "content/public/browser/navigation_details.h"
 #include "content/public/browser/navigation_entry.h"
+#include "content/public/browser/user_metrics.h"
 #include "content/public/browser/web_contents.h"
 
 // Macro to log UMA statistics related to the 8 tiles shown on the NTP.
@@ -33,6 +34,16 @@ enum SuggestionsType {
 const char kImpressionHistogramWithProvider[] =
     "NewTabPage.SuggestionsImpression.%s";
 
+// Number of Most Visited elements on the NTP for logging purposes.
+const int kNumMostVisited = 8;
+
+// Name of the histogram keeping track of Most Visited clicks.
+const char kMostVisitedHistogramName[] = "NewTabPage.MostVisited";
+
+// Format string to generate the name for the histogram keeping track of
+// suggestion clicks.
+const char kMostVisitedHistogramWithProvider[] = "NewTabPage.MostVisited.%s";
+
 }  // namespace
 
 DEFINE_WEB_CONTENTS_USER_DATA_KEY(NTPUserDataLogger);
@@ -58,6 +69,13 @@ NTPUserDataLogger* NTPUserDataLogger::GetOrCreateFromWebContents(
   return logger;
 }
 
+// static
+std::string NTPUserDataLogger::GetHistogramNameForProvider(

[beaudoin, 2014/03/04 21:33:15]

GetNavigationHistogramNameForProvider(

Maybe add GetImpressionHistogramNameForProvider?

[huangs, 2014/03/04 22:10:43]

Done; added GetImpressionHistogramNameForProvider() and using it below.

+    const std::string& provider) {
+  return base::StringPrintf(kMostVisitedHistogramWithProvider,
+                            provider.c_str());
+}
+
 void NTPUserDataLogger::EmitNtpStatistics() {
   UMA_HISTOGRAM_COUNTS("NewTabPage.NumberOfMouseOvers", number_of_mouseovers_);
   number_of_mouseovers_ = 0;
@@ -143,12 +161,37 @@ void NTPUserDataLogger::LogImpression(int position,
   base::HistogramBase* counter = base::LinearHistogram::FactoryGet(
       base::StringPrintf(kImpressionHistogramWithProvider,
                          base::UTF16ToUTF8(provider).c_str()),
-      1, MostVisitedIframeSource::kNumMostVisited,
-      MostVisitedIframeSource::kNumMostVisited + 1,
+      1,
+      kNumMostVisited,
+      kNumMostVisited + 1,
       base::Histogram::kUmaTargetedHistogramFlag);
   counter->Add(position);

[beaudoin, 2014/03/04 21:33:15]

I'd be tempted to use the exact same pattern as below here:
Always log on NewTabPage.SuggestionsImpression and log on
NewTabPage.SuggestionsImpression.%s if a provider is specified.
(We have reserved NewTabPage.SuggestionsImpression but nobody ever logs on it.
:\)

[huangs, 2014/03/04 22:10:43]

Done; added kImpressionHistogramName.

Note that the routines are not identical: this one does not have 

content::RecordAction(base::UserMetricsAction(...));

at bottom.

 }
 
+void NTPUserDataLogger::LogNavigation(int position,
+                                      const base::string16& provider) {
+  // Log the Most Visited navigation.

[beaudoin, 2014/03/04 21:33:15]

for both navigations that have providers and those that dont.

[huangs, 2014/03/04 22:10:43]

Done.

+  UMA_HISTOGRAM_ENUMERATION(kMostVisitedHistogramName, position,
+                            kNumMostVisited);
+
+  // If a provider is specified, log the metric specific to it.
+  if (!provider.empty()) {
+    // Cannot rely on UMA histograms macro because the name of the histogram is
+    // generated dynamically.
+    base::HistogramBase* counter = base::LinearHistogram::FactoryGet(
+        GetHistogramNameForProvider(base::UTF16ToUTF8(provider)),
+        1,
+        kNumMostVisited,
+        kNumMostVisited + 1,
+        base::Histogram::kUmaTargetedHistogramFlag);
+    counter->Add(position);
+  }
+
+  // Records the action. This will be available as a time-stamped stream
+  // server-side and can be used to compute time-to-long-dwell.
+  content::RecordAction(base::UserMetricsAction("MostVisited_Clicked"));
+}
+
 // content::WebContentsObserver override
 void NTPUserDataLogger::NavigationEntryCommitted(
     const content::LoadCommittedDetails& load_details) {