Prefetching: Introduce store commands abstractions to be used by tasks.

components/offline_pages/core/prefetch/prefetch_dispatcher.h

Index: components/offline_pages/core/prefetch/prefetch_dispatcher.h
diff --git a/components/offline_pages/core/prefetch/prefetch_dispatcher.h b/components/offline_pages/core/prefetch/prefetch_dispatcher.h
index f5e0d636f1bdec313ac1e3b8d7e6e619f4cb114d..033cd5451948f467a7fff2be0899b81d706b4440 100644
--- a/components/offline_pages/core/prefetch/prefetch_dispatcher.h
+++ b/components/offline_pages/core/prefetch/prefetch_dispatcher.h
@@ -45,6 +45,7 @@ class PrefetchDispatcher {
   // with the client's unique namespace. URLs that are currently in the system
   // for this client are acceptable but ignored.
   virtual void AddCandidatePrefetchURLs(
+      const std::string& name_space,
       const std::vector<PrefetchURL>& prefetch_urls) = 0;
 
   // Called when all existing suggestions are no longer considered valid for a