Enable Oilpan by default in modules/filesystem/

Source/modules/filesystem/WorkerGlobalScopeFileSystem.h

Index: Source/modules/filesystem/WorkerGlobalScopeFileSystem.h
diff --git a/Source/modules/filesystem/WorkerGlobalScopeFileSystem.h b/Source/modules/filesystem/WorkerGlobalScopeFileSystem.h
index 869608f15edeae2e5d02c690de104c074c620c64..a2fa8deced071b6d3756a4f521a44dea2578d294 100644
--- a/Source/modules/filesystem/WorkerGlobalScopeFileSystem.h
+++ b/Source/modules/filesystem/WorkerGlobalScopeFileSystem.h
@@ -47,9 +47,9 @@ public:
     };
 
     static void webkitRequestFileSystem(WorkerGlobalScope&, int type, long long size, PassOwnPtr<FileSystemCallback> successCallback, PassOwnPtr<ErrorCallback>);
-    static PassRefPtrWillBeRawPtr<DOMFileSystemSync> webkitRequestFileSystemSync(WorkerGlobalScope&, int type, long long size, ExceptionState&);
+    static DOMFileSystemSync* webkitRequestFileSystemSync(WorkerGlobalScope&, int type, long long size, ExceptionState&);
     static void webkitResolveLocalFileSystemURL(WorkerGlobalScope&, const String& url, PassOwnPtr<EntryCallback> successCallback, PassOwnPtr<ErrorCallback>);
-    static PassRefPtrWillBeRawPtr<EntrySync> webkitResolveLocalFileSystemSyncURL(WorkerGlobalScope&, const String& url, ExceptionState&);
+    static EntrySync* webkitResolveLocalFileSystemSyncURL(WorkerGlobalScope&, const String& url, ExceptionState&);
 
 private:
     WorkerGlobalScopeFileSystem();