Update MostVisitedSites observer interface.

chrome/browser/android/ntp/popular_sites.cc

Index: chrome/browser/android/ntp/popular_sites.cc
diff --git a/chrome/browser/android/ntp/popular_sites.cc b/chrome/browser/android/ntp/popular_sites.cc
index be7e3e415ded77ffb948ef758cc57ce2c404c894..76f3230dae4662a18e0d4f85105ea0b195652546 100644
--- a/chrome/browser/android/ntp/popular_sites.cc
+++ b/chrome/browser/android/ntp/popular_sites.cc
@@ -164,20 +164,21 @@ std::unique_ptr<std::vector<PopularSites::Site>> ReadAndParseJsonFile(
 
 }  // namespace
 
-PopularSites::Site::Site(const base::string16& title,
-                         const GURL& url,
-                         const GURL& favicon_url,
-                         const GURL& large_icon_url,
-                         const GURL& thumbnail_url)
+PopularSites_Site::PopularSites_Site(const base::string16& title,
+                                     const GURL& url,
+                                     const GURL& favicon_url,
+                                     const GURL& large_icon_url,
+                                     const GURL& thumbnail_url)
     : title(title),
       url(url),
       favicon_url(favicon_url),
       large_icon_url(large_icon_url),
       thumbnail_url(thumbnail_url) {}
 
-PopularSites::Site::Site(const Site& other) = default;
+PopularSites_Site::PopularSites_Site(const PopularSites_Site& other)
+  = default;
 
-PopularSites::Site::~Site() {}
+PopularSites_Site::~PopularSites_Site() {}
 
 PopularSites::PopularSites(Profile* profile,
                            const std::string& override_country,