原因：没有找到对应的MenuScene.cpp文件。
LOCAL_SRC_FILES := hellocpp/main.cpp \
../../Classes/AppDelegate.cpp \
../../Classes/HelloWorldScene.cpp
改成
LOCAL_SRC_FILES := hellocpp/main.cpp \
../../Classes/AppDelegate.cpp \
../../Classes/HelloWorldScene.cpp \
../../Classes/MenuScene.cpp \
../../Classes/StartScene.cpp \
../../Classes/TopMenu.cpp \ ../../Classes/GameLayer.cpp \ ../../Classes/GameScene.cpp \ ../../Classes/WelcomeLayer.cpp \ ../../Classes/WelcomeScene.cpp \ ../../Classes/GameData.cpp \
