Oilpan: have Storage objects reside on the heap by default.

Source/modules/storage/StorageNamespace.cpp

Index: Source/modules/storage/StorageNamespace.cpp
diff --git a/Source/modules/storage/StorageNamespace.cpp b/Source/modules/storage/StorageNamespace.cpp
index 4725cd4a891a9430942adf4fd0d31b463d62609d..e7ed59eb11b71838c30a3a42410aa7f413bbc474 100644
--- a/Source/modules/storage/StorageNamespace.cpp
+++ b/Source/modules/storage/StorageNamespace.cpp
@@ -44,7 +44,7 @@ StorageNamespace::~StorageNamespace()
 {
 }
 
-PassOwnPtrWillBeRawPtr<StorageArea> StorageNamespace::localStorageArea(SecurityOrigin* origin)
+StorageArea* StorageNamespace::localStorageArea(SecurityOrigin* origin)
 {
     ASSERT(isMainThread());
     static WebStorageNamespace* localStorageNamespace = nullptr;
@@ -53,7 +53,7 @@ PassOwnPtrWillBeRawPtr<StorageArea> StorageNamespace::localStorageArea(SecurityO
     return StorageArea::create(adoptPtr(localStorageNamespace->createStorageArea(origin->toString())), LocalStorage);
 }
 
-PassOwnPtrWillBeRawPtr<StorageArea> StorageNamespace::storageArea(SecurityOrigin* origin)
+StorageArea* StorageNamespace::storageArea(SecurityOrigin* origin)
 {
     return StorageArea::create(adoptPtr(m_webStorageNamespace->createStorageArea(origin->toString())), SessionStorage);
 }