Issue 5552 - use strict mode for all JS in libadblocklus

test/GlobalJsObject.cpp

 /*
  * 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
@@ skipping 16 matching lines @@
     {
       ThrowingPlatformCreationParameters params;
       params.timer = AdblockPlus::CreateDefaultTimer();
       platform.reset(new AdblockPlus::Platform(std::move(params)));
     }
   };
 }
 
 TEST_F(GlobalJsObjectTest, SetTimeout)
 {
-  GetJsEngine().Evaluate("setTimeout(function() {foo = 'bar';}, 100)");
-  ASSERT_TRUE(GetJsEngine().Evaluate("this.foo").IsUndefined());
+  GetJsEngine().Evaluate("let foo; setTimeout(function() {foo = 'bar';}, 100)");
+  ASSERT_TRUE(GetJsEngine().Evaluate("foo").IsUndefined());
   AdblockPlus::Sleep(200);
-  ASSERT_EQ("bar", GetJsEngine().Evaluate("this.foo").AsString());
+  ASSERT_EQ("bar", GetJsEngine().Evaluate("foo").AsString());
 }
 
 TEST_F(GlobalJsObjectTest, SetTimeoutWithArgs)
 {
-  GetJsEngine().Evaluate("setTimeout(function(s) {foo = s;}, 100, 'foobar')");
-  ASSERT_TRUE(GetJsEngine().Evaluate("this.foo").IsUndefined());
+  GetJsEngine().Evaluate("let foo; setTimeout(function(s) {foo = s;}, 100, 'foobar')");
+  ASSERT_TRUE(GetJsEngine().Evaluate("foo").IsUndefined());
   AdblockPlus::Sleep(200);
-  ASSERT_EQ("foobar", GetJsEngine().Evaluate("this.foo").AsString());
+  ASSERT_EQ("foobar", GetJsEngine().Evaluate("foo").AsString());
 }
 
 TEST_F(GlobalJsObjectTest, SetTimeoutWithInvalidArgs)
 {
   ASSERT_ANY_THROW(GetJsEngine().Evaluate("setTimeout()"));
   ASSERT_ANY_THROW(GetJsEngine().Evaluate("setTimeout('', 1)"));
 }
 
 TEST_F(GlobalJsObjectTest, SetMultipleTimeouts)
 {
-  GetJsEngine().Evaluate("foo = []");
+  GetJsEngine().Evaluate("let foo = []");
   GetJsEngine().Evaluate("setTimeout(function(s) {foo.push('1');}, 100)");
   GetJsEngine().Evaluate("setTimeout(function(s) {foo.push('2');}, 150)");
   AdblockPlus::Sleep(200);
-  ASSERT_EQ("1,2", GetJsEngine().Evaluate("this.foo").AsString());
+  ASSERT_EQ("1,2", GetJsEngine().Evaluate("foo").AsString());
 }