Make LevelDBObserver an associated interface to LevelDBWrapper.

content/renderer/dom_storage/local_storage_cached_area.cc

Index: content/renderer/dom_storage/local_storage_cached_area.cc
diff --git a/content/renderer/dom_storage/local_storage_cached_area.cc b/content/renderer/dom_storage/local_storage_cached_area.cc
index 57f37ea8417f3591545349ece233d1a432af891e..e2e4f3b51df3fb5fb41f616f6e225905a63f00ca 100644
--- a/content/renderer/dom_storage/local_storage_cached_area.cc
+++ b/content/renderer/dom_storage/local_storage_cached_area.cc
@@ -57,9 +57,11 @@ LocalStorageCachedArea::LocalStorageCachedArea(
     LocalStorageCachedAreas* cached_areas)
     : origin_(origin), binding_(this),
       cached_areas_(cached_areas), weak_factory_(this) {
-  storage_partition_service->OpenLocalStorage(
-      origin_, binding_.CreateInterfacePtrAndBind(),
-      mojo::MakeRequest(&leveldb_));
+  storage_partition_service->OpenLocalStorage(origin_,
+                                              mojo::MakeRequest(&leveldb_));
+  mojom::LevelDBObserverAssociatedPtrInfo ptr_info;
+  binding_.Bind(&ptr_info, leveldb_.associated_group());
+  leveldb_->AddObserver(std::move(ptr_info));
 }
 
 LocalStorageCachedArea::~LocalStorageCachedArea() {