Field trial removing tiles from NTP if URL is already open - for 1993 clients

chrome/browser/ui/search/instant_page.cc

Index: chrome/browser/ui/search/instant_page.cc
diff --git a/chrome/browser/ui/search/instant_page.cc b/chrome/browser/ui/search/instant_page.cc
index 9177352ceaf91302af700ebf926b2036c93d1002..0beacb91b827a9b13e2fa6c38a0f9239f61b836e 100644
--- a/chrome/browser/ui/search/instant_page.cc
+++ b/chrome/browser/ui/search/instant_page.cc
@@ -7,13 +7,17 @@
 #include "apps/app_launcher.h"
 #include "base/strings/utf_string_conversions.h"
 #include "chrome/browser/chrome_notification_types.h"
+#include "chrome/browser/history/most_visited_tiles_experiment.h"
+#include "chrome/browser/history/top_sites.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/search/instant_service.h"
 #include "chrome/browser/search/instant_service_factory.h"
 #include "chrome/browser/search/search.h"
+#include "chrome/browser/ui/browser_finder.h"
 #include "chrome/browser/ui/search/instant_tab.h"
 #include "chrome/browser/ui/search/search_model.h"
 #include "chrome/browser/ui/search/search_tab_helper.h"
+#include "chrome/browser/ui/tabs/tab_strip_model.h"
 #include "chrome/common/render_messages.h"
 #include "chrome/common/url_constants.h"
 #include "content/public/browser/navigation_controller.h"
@@ -26,6 +30,21 @@
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/gfx/font.h"
 
+namespace {
+
+// Creates a set containing the canonical URLs of the currently open tabs.
+void GetOpenUrls(const TabStripModel& tabs,
+                 const history::TopSites& top_sites,
+                 std::set<std::string>* urls) {
+  for (int i = 0; i < tabs.count(); ++i) {
+    content::WebContents* web_contents = tabs.GetWebContentsAt(i);
+    if (web_contents)
+      urls->insert(top_sites.GetCanonicalURLString(web_contents->GetURL()));
+  }
+}
+
+}  // namespace
+
 InstantPage::Delegate::~Delegate() {
 }
 
@@ -187,7 +206,10 @@ void InstantPage::ThemeInfoChanged(const ThemeBackgroundInfo& theme_info) {
 
 void InstantPage::MostVisitedItemsChanged(
     const std::vector<InstantMostVisitedItem>& items) {
-  sender()->SendMostVisitedItems(items);
+  std::vector<InstantMostVisitedItem> items_copy(items);
+  MaybeRemoveMostVisitedItems(&items_copy);
+
+  sender()->SendMostVisitedItems(items_copy);
 
   content::NotificationService::current()->Notify(
       chrome::NOTIFICATION_INSTANT_SENT_MOST_VISITED_ITEMS,
@@ -283,3 +305,31 @@ void InstantPage::ClearContents() {
   sender()->SetContents(NULL);
   Observe(NULL);
 }
+
+void InstantPage::MaybeRemoveMostVisitedItems(
+    std::vector<InstantMostVisitedItem>* items) {
+// The following #if is due to the facts that tabstripmodel cannot be accessed
+// in the same way, that chrome::FindBrowserWithProfile is undefined in Android
+// and, moreover, that this experiment is not designed to run on Android devices
+// due to different NTP presentation.
+#if !defined(OS_ANDROID)
+  if (!history::MostVisitedTilesExperiment::IsDontShowOpenURLsEnabled()) {
+    return;
+  }
+
+  TabStripModel* tab_strip_model = chrome::FindBrowserWithProfile(
+      profile_,
+      chrome::GetActiveDesktop())->tab_strip_model();
+  history::TopSites* top_sites = profile_->GetTopSites();
+  if (!tab_strip_model || !top_sites) {
+    NOTREACHED();
+    return;
+  }
+
+  std::set<std::string> open_urls;
+  GetOpenUrls(*tab_strip_model, *top_sites, &open_urls);
+  history::MostVisitedTilesExperiment::RemoveItemsMatchingOpenTabs(
+      open_urls, items);
+
+#endif
+}