Log NTP hovers in 1993 clients

chrome/browser/ui/search/instant_ntp.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/ui/search/instant_ntp.h"
 
+#include "base/metrics/histogram.h"
+#include "chrome/browser/search/search.h"
 #include "chrome/browser/ui/search/search_tab_helper.h"
+#include "content/public/browser/navigation_details.h"
 #include "content/public/browser/navigation_entry.h"
 #include "content/public/browser/web_contents.h"
+#include "content/public/browser/web_contents_observer.h"
+#include "content/public/browser/web_contents_user_data.h"
+
+namespace {
+
+// Helper class for logging data from the NTP. Attached to each InstantNTP
+// instance.
+class NTPLoggingUserData
+    : public content::WebContentsObserver,
+      public content::WebContentsUserData<NTPLoggingUserData> {
+ public:
+  virtual ~NTPLoggingUserData() {}
+
+  // Called each time the mouse hovers over an iframe or title.
+  void increment_number_of_mouseovers() {
+    number_of_mouseovers_++;
+  }
+
+  void set_instant_url(const GURL& url) {
+    instant_url_ = url;
+  }
+
+  // Logs total number of mouseovers per NTP session to UMA histogram. Called
+  // when an NTP tab is about to be deactivated (be it by switching tabs, losing
+  // focus or closing the tab/shutting down Chrome) or when the user navigates
+  // to a URL.
+  void EmitMouseoverCount() {
+    UMA_HISTOGRAM_COUNTS("NewTabPage.NumberOfMouseOvers",
+                         number_of_mouseovers_);
+    number_of_mouseovers_ = 0;
+  }
+
+  // content::WebContentsObserver override
+  virtual void NavigationEntryCommitted OVERRIDE(
+      const content::LoadCommittedDetails& load_details) {
+    if (!load_details.previous_url.is_valid())
+      return;
+
+    if (chrome::MatchesOriginAndPath(instant_url_, load_details.previous_url))
+      EmitMouseoverCount();
+  }
+
+ private:
+  explicit NTPLoggingUserData(content::WebContents* contents)
+      : content::WebContentsObserver(contents),
+        number_of_mouseovers_(0) {}
+  friend class content::WebContentsUserData<NTPLoggingUserData>;
+
+  int number_of_mouseovers_;
+  GURL instant_url_;
+
+  DISALLOW_COPY_AND_ASSIGN(NTPLoggingUserData);
+};
+
+}  // namespace
+
+DEFINE_WEB_CONTENTS_USER_DATA_KEY(NTPLoggingUserData);
 
 InstantNTP::InstantNTP(InstantPage::Delegate* delegate,
                        const std::string& instant_url,
                        bool is_incognito)
     : InstantPage(delegate, instant_url, is_incognito),
       loader_(this) {
 }
 
 InstantNTP::~InstantNTP() {
 }
 
 void InstantNTP::InitContents(Profile* profile,
                               const content::WebContents* active_tab,
                               const base::Closure& on_stale_callback) {
   loader_.Init(GURL(instant_url()), profile, active_tab, on_stale_callback);

[Alexei Svitkine (slow), 2013/06/28 20:15:34]

Nit: Extract GURL(instant_url()) into a variable, since you use it in two places
in this function.

[annark1, 2013/06/28 20:47:27]

Done.

   SetContents(loader_.contents());
   SearchTabHelper::FromWebContents(contents())->InitForPreloadedNTP();
+
+  NTPLoggingUserData::CreateForWebContents(contents());
+  NTPLoggingUserData::FromWebContents(
+      contents())->set_instant_url(GURL(instant_url()));
+
   loader_.Load();
 }
 
 scoped_ptr<content::WebContents> InstantNTP::ReleaseContents() {
   SetContents(NULL);
   return loader_.ReleaseContents();
 }
 
+// static
+void InstantNTP::CountMouseover(content::WebContents* contents) {
+  if (NTPLoggingUserData* data = NTPLoggingUserData::FromWebContents(
+      contents)) {

[Alexei Svitkine (slow), 2013/06/28 20:15:34]

Nit: Indent 4 more.

[annark1, 2013/06/28 20:47:27]

Done.

+    data->increment_number_of_mouseovers();
+  }
+}
+
+// static
+void InstantNTP::EmitMouseoverCount(content::WebContents* contents) {
+  if (NTPLoggingUserData* data = NTPLoggingUserData::FromWebContents(
+      contents)) {

[Alexei Svitkine (slow), 2013/06/28 20:15:34]

Nit: Indent 4 more.

[annark1, 2013/06/28 20:47:27]

Done.

+    data->EmitMouseoverCount();
+  }
+}
+
 void InstantNTP::OnSwappedContents() {
   SetContents(loader_.contents());
 }
 
 void InstantNTP::OnFocus() {
   NOTREACHED();
 }
 
 void InstantNTP::OnMouseDown() {
   NOTREACHED();
@@ skipping 12 matching lines @@
 void InstantNTP::LoadCompletedMainFrame() {
 }
 
 bool InstantNTP::ShouldProcessRenderViewCreated() {
   return true;
 }
 
 bool InstantNTP::ShouldProcessRenderViewGone() {
   return true;
 }