Add API calls and stubs for filter matching and subscription management

test/FilterEngineStubs.cpp

+#include <AdblockPlus.h>
+#include <fstream>
+#include <gtest/gtest.h>
+#include <sstream>
+
+TEST(FilterEngineStubsTest, AddRemove)
+{
+  AdblockPlus::JsEngine jsEngine(0, 0);
+  AdblockPlus::FilterEngine filterEngine(jsEngine);
+  ASSERT_EQ(filterEngine.GetSubscriptions().size(), 0);
+  AdblockPlus::Subscription subscription("foo", "bar");
+  filterEngine.AddSubscription(subscription);
+  ASSERT_EQ(filterEngine.GetSubscriptions().size(), 1);
+  filterEngine.RemoveSubscription(subscription);
+  ASSERT_EQ(filterEngine.GetSubscriptions().size(), 0);
+}
+
+TEST(FilterEngineStubsTest, Matches)
+{
+  AdblockPlus::JsEngine jsEngine(0, 0);
+  AdblockPlus::FilterEngine filterEngine(jsEngine);
+  filterEngine.AddSubscription(AdblockPlus::Subscription("foo", "bar"));
+  ASSERT_FALSE(filterEngine.Matches("http://example.org/a", ""));
+  ASSERT_TRUE(filterEngine.Matches("http://example.org/ad", ""));
+}