title: iOS Google map - How to know when user begins or stop drag map
body: <p>I'm developing with <code>Google map SDK 6.1</code> .I want to know when user begin drag or stop drag the map, I just found 2 delegate function : <code>didChangeCameraPosition</code> and <code>idleAtCameraPosition</code>. Is there a way to catch when user begin or stop drag the map?</p>