Issue #3593 - Stop sharing a single isolate amongst all unit tests

test/FilterEngine.cpp

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
  * Copyright (C) 2006-2016 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
@@ skipping 39 matching lines @@
       jsEngine->SetLogSystem(AdblockPlus::LogSystemPtr(new LogSystem));
       filterEngine = FilterEnginePtr(new AdblockPlus::FilterEngine(jsEngine));
     }
 
     void TearDown()
     {
       if (webRequest)
       {
         webRequest->Cancel();
       }
+      webRequest.reset();
+      filterEngine.reset();
+      BaseJsTest::TearDown();
     }
   };
 
   typedef FilterEngineTestGeneric<LazyFileSystem, AdblockPlus::DefaultLogSystem> FilterEngineTest;
   typedef FilterEngineTestGeneric<VeryLazyFileSystem, LazyLogSystem> FilterEngineTestNoData;
 
   struct MockFilterChangeCallback
   {
     MockFilterChangeCallback(int& timesCalled) : timesCalled(timesCalled) {}
 
@@ skipping 560 matching lines @@
 
 TEST_F(FilterEngineWithFreshFolder, DisableSubscriptionsAutoSelectOnFirstRun)
 {
   auto jsEngine = createJsEngine();
   FilterEngine::Prefs preSettings;
   preSettings["first_run_subscription_auto_select"] = jsEngine->NewValue(false);
   auto filterEngine = FilterEnginePtr(new AdblockPlus::FilterEngine(jsEngine, preSettings));
   const auto subscriptions = filterEngine->GetListedSubscriptions();
   EXPECT_EQ(0u, subscriptions.size());
 }