Reland: Start checking URLs using PVer4. Verdict not returned to client yet.

components/safe_browsing_db/v4_local_database_manager.cc

Index: components/safe_browsing_db/v4_local_database_manager.cc
diff --git a/components/safe_browsing_db/v4_local_database_manager.cc b/components/safe_browsing_db/v4_local_database_manager.cc
index 9215dc72288f63ac34bf874e4632b7d2ff907a8c..28320252fec77167878326768d915c7ef53f9ae8 100644
--- a/components/safe_browsing_db/v4_local_database_manager.cc
+++ b/components/safe_browsing_db/v4_local_database_manager.cc
@@ -12,6 +12,8 @@
 #include "base/bind_helpers.h"
 #include "base/callback.h"
 #include "base/memory/ptr_util.h"
+#include "base/memory/ref_counted.h"
+#include "components/safe_browsing_db/v4_feature_list.h"
 #include "content/public/browser/browser_thread.h"
 
 using content::BrowserThread;
@@ -64,6 +66,16 @@ V4LocalDatabaseManager::PendingCheck::PendingCheck(
 
 V4LocalDatabaseManager::PendingCheck::~PendingCheck() {}
 
+// static
+scoped_refptr<V4LocalDatabaseManager> V4LocalDatabaseManager::Create(
+    const base::FilePath& base_path) {
+  if (!V4FeatureList::IsLocalDatabaseManagerEnabled()) {
+    return nullptr;
+  }
+
+  return make_scoped_refptr(new V4LocalDatabaseManager(base_path));
+}
+
 V4LocalDatabaseManager::V4LocalDatabaseManager(const base::FilePath& base_path)
     : base_path_(base_path), enabled_(false), list_infos_(GetListInfos()) {
   DCHECK(!base_path_.empty());