Pass PopularSites ownership to MostVisitedSites.

Nothing outside of MostVisitedSites needs to use it.

Review-Url: https://codereview.chromium.org/2337893003
Cr-Commit-Position: refs/heads/master@{#418625}

chrome/browser/android/ntp/most_visited_sites_bridge.cc

@@ -12,6 +12,7 @@
 #include "base/android/scoped_java_ref.h"
 #include "base/bind.h"
 #include "base/callback.h"
+#include "base/memory/ptr_util.h"
 #include "chrome/browser/android/ntp/popular_sites.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/history/top_sites_factory.h"
@@ -158,17 +159,17 @@ void MostVisitedSitesBridge::JavaObserver::OnPopularURLsAvailable(
 
 MostVisitedSitesBridge::MostVisitedSitesBridge(Profile* profile)
     : supervisor_(profile),
-      popular_sites_(BrowserThread::GetBlockingPool(),
+      most_visited_(profile->GetPrefs(),
+                    TopSitesFactory::GetForProfile(profile),
+                    SuggestionsServiceFactory::GetForProfile(profile),
+                    base::MakeUnique<ntp_tiles::PopularSites>(
+                        BrowserThread::GetBlockingPool(),
                         profile->GetPrefs(),
                         TemplateURLServiceFactory::GetForProfile(profile),
                         g_browser_process->variations_service(),
                         profile->GetRequestContext(),
                         ChromePopularSites::GetDirectory(),
                         base::Bind(safe_json::SafeJsonParser::Parse)),
-      most_visited_(profile->GetPrefs(),
-                    TopSitesFactory::GetForProfile(profile),
-                    SuggestionsServiceFactory::GetForProfile(profile),
-                    &popular_sites_,
                     &supervisor_) {
   // Register the thumbnails debugging page.
   // TODO(sfiera): find thumbnails a home. They don't belong here.

chrome/browser/android/ntp/most_visited_sites_bridge.h

@@ -83,7 +83,6 @@ class MostVisitedSitesBridge {
   };
   SupervisorBridge supervisor_;
 
-  ntp_tiles::PopularSites popular_sites_;
   ntp_tiles::MostVisitedSites most_visited_;
 
   DISALLOW_COPY_AND_ASSIGN(MostVisitedSitesBridge);

components/ntp_tiles/most_visited_sites.cc

@@ -143,12 +143,12 @@ std::string GetSourceHistogramName(int source) {
 MostVisitedSites::MostVisitedSites(PrefService* prefs,
                                    scoped_refptr<history::TopSites> top_sites,
                                    SuggestionsService* suggestions,
-                                   PopularSites* popular_sites,
+                                   std::unique_ptr<PopularSites> popular_sites,
                                    MostVisitedSitesSupervisor* supervisor)
     : prefs_(prefs),
       top_sites_(top_sites),
       suggestions_service_(suggestions),
-      popular_sites_(popular_sites),
+      popular_sites_(std::move(popular_sites)),
       supervisor_(supervisor),
       observer_(nullptr),
       num_sites_(0),

components/ntp_tiles/most_visited_sites.h

@@ -119,7 +119,7 @@ class MostVisitedSites : public history::TopSitesObserver,
   MostVisitedSites(PrefService* prefs,
                    scoped_refptr<history::TopSites> top_sites,
                    suggestions::SuggestionsService* suggestions,
-                   PopularSites* popular_sites,
+                   std::unique_ptr<PopularSites> popular_sites,
                    MostVisitedSitesSupervisor* supervisor);
 
   ~MostVisitedSites() override;
@@ -195,7 +195,7 @@ class MostVisitedSites : public history::TopSitesObserver,
   PrefService* prefs_;
   scoped_refptr<history::TopSites> top_sites_;
   suggestions::SuggestionsService* suggestions_service_;
-  PopularSites* const popular_sites_;
+  std::unique_ptr<PopularSites> const popular_sites_;
   MostVisitedSitesSupervisor* supervisor_;
 
   Observer* observer_;