iOS OpenGL refactoring

in apple documentation written that OpenGL buffers must cleared on layoutSubview but created only on next frame layoutSubview can call several time on one frame and sometimes [context_ renderbufferStorage:GL_RENDERBUFFER fromDrawable:layer] return false and picture freeze.
For example if you game is landscape, and you use banner or interstitials user click on it, StoreWindows opens(on iPhone it is only portrait) after go back picture freeze on last frame.