Rename ErrorCallback into LogSystem, provide a proper console API

test/JsEngine.cpp

Index: test/JsEngine.cpp
===================================================================
--- a/test/JsEngine.cpp
+++ b/test/JsEngine.cpp
@@ -62,21 +62,21 @@ TEST_F(JsEngineTest, ValueCreation)
   ASSERT_TRUE(value->IsObject());
   ASSERT_EQ(0u, value->GetOwnPropertyNames().size());
 }
 
 TEST(NewJsEngineTest, CallbackGetSet)
 {
   AdblockPlus::JsEnginePtr jsEngine(AdblockPlus::JsEngine::New());
 
-  ASSERT_TRUE(jsEngine->GetErrorCallback());
-  ASSERT_ANY_THROW(jsEngine->SetErrorCallback(AdblockPlus::ErrorCallbackPtr()));
-  AdblockPlus::ErrorCallbackPtr errorCallback(new AdblockPlus::DefaultErrorCallback());
-  jsEngine->SetErrorCallback(errorCallback);
-  ASSERT_EQ(errorCallback, jsEngine->GetErrorCallback());
+  ASSERT_TRUE(jsEngine->GetLogSystem());
+  ASSERT_ANY_THROW(jsEngine->SetLogSystem(AdblockPlus::LogSystemPtr()));
+  AdblockPlus::LogSystemPtr logSystem(new AdblockPlus::DefaultLogSystem());
+  jsEngine->SetLogSystem(logSystem);
+  ASSERT_EQ(logSystem, jsEngine->GetLogSystem());
 
   ASSERT_TRUE(jsEngine->GetFileSystem());
   ASSERT_ANY_THROW(jsEngine->SetFileSystem(AdblockPlus::FileSystemPtr()));
   AdblockPlus::FileSystemPtr fileSystem(new AdblockPlus::DefaultFileSystem());
   jsEngine->SetFileSystem(fileSystem);
   ASSERT_EQ(fileSystem, jsEngine->GetFileSystem());
 
   ASSERT_TRUE(jsEngine->GetWebRequest());