Remove legacy popular sites cache cleaning

ios/chrome/browser/ntp_tiles/ios_popular_sites_factory.cc

Index: ios/chrome/browser/ntp_tiles/ios_popular_sites_factory.cc
diff --git a/ios/chrome/browser/ntp_tiles/ios_popular_sites_factory.cc b/ios/chrome/browser/ntp_tiles/ios_popular_sites_factory.cc
index 8449dd95ff2377a55fd93a3295c1302b6d13b32e..58e87b32e136ecee8a7d9b6a775593fbb6c7fa75 100644
--- a/ios/chrome/browser/ntp_tiles/ios_popular_sites_factory.cc
+++ b/ios/chrome/browser/ntp_tiles/ios_popular_sites_factory.cc
@@ -7,25 +7,20 @@
 #include "base/bind.h"
 #include "base/files/file_path.h"
 #include "base/memory/ptr_util.h"
-#include "base/path_service.h"
-#include "base/threading/sequenced_worker_pool.h"
 #include "components/ntp_tiles/json_unsafe_parser.h"
 #include "components/ntp_tiles/popular_sites_impl.h"
 #include "ios/chrome/browser/application_context.h"
 #include "ios/chrome/browser/browser_state/chrome_browser_state.h"
-#include "ios/chrome/browser/chrome_paths.h"
 #include "ios/chrome/browser/search_engines/template_url_service_factory.h"
 #include "ios/web/public/web_thread.h"
 
 std::unique_ptr<ntp_tiles::PopularSites>
 IOSPopularSitesFactory::NewForBrowserState(
     ios::ChromeBrowserState* browser_state) {
-  base::FilePath popular_sites_path;
-  base::PathService::Get(ios::DIR_USER_DATA, &popular_sites_path);
   return base::MakeUnique<ntp_tiles::PopularSitesImpl>(
-      web::WebThread::GetBlockingPool(), browser_state->GetPrefs(),
+      browser_state->GetPrefs(),
       ios::TemplateURLServiceFactory::GetForBrowserState(browser_state),
       GetApplicationContext()->GetVariationsService(),
-      browser_state->GetRequestContext(), popular_sites_path,
+      browser_state->GetRequestContext(),
       base::Bind(ntp_tiles::JsonUnsafeParser::Parse));
 }