fixed #2040: Getting scale property from sub-ccb node may trigger an assert of 'CCAssert( m_fScaleX == m_fScaleY, "CCNode#scale. ScaleX != ScaleY. Don't know which one to return");'.
Merge pull request #2368 from dumganhar/iss2040-ccb-getScale

fixed #2040: Getting scale property from sub-ccb node may trigger an assert of 'CCAssert( m_fScaleX == m_fScaleY, "CCNode#scale. ScaleX != ScaleY. Don't know which one to return");'.