Issue 5137 - [emscripten] Added basic filter storage implementation

compiled/storage/FilterStorage.h

Index: compiled/storage/FilterStorage.h
===================================================================
new file mode 100644
--- /dev/null
+++ b/compiled/storage/FilterStorage.h
@@ -0,0 +1,33 @@
+/*
+ * This file is part of Adblock Plus <https://adblockplus.org/>,
+ * Copyright (C) 2006-2017 eyeo GmbH
+ *
+ * Adblock Plus is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 3 as
+ * published by the Free Software Foundation.
+ *
+ * Adblock Plus is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Adblock Plus.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#include "../subscription/Subscription.h"
+
+namespace FilterStorage
+{
+  EMSCRIPTEN_KEEPALIVE unsigned int GetSubscriptionCount();
+  EMSCRIPTEN_KEEPALIVE Subscription* SubscriptionAt(unsigned int index);
+  EMSCRIPTEN_KEEPALIVE int IndexOfSubscription(const Subscription* subscription);
+  EMSCRIPTEN_KEEPALIVE Subscription* GetSubscriptionForFilter(
+        const Filter* filter);
+  EMSCRIPTEN_KEEPALIVE bool AddSubscription(Subscription* subscription);
+  EMSCRIPTEN_KEEPALIVE bool RemoveSubscription(Subscription* subscription);
+  EMSCRIPTEN_KEEPALIVE bool MoveSubscription(Subscription* subscription,
+      const Subscription* insertBefore);
+}