iOS 9.0.x bug automaticallyAdjustsScrollViewInsets doesn't change insets on iOS 9

iosVersionRelatedBugFix.swift

        #if os(iOS)
            // temp fix for iOS 9.0.x http://www.openradar.me/22106545
            let os = NSProcessInfo().operatingSystemVersion
            switch (os.majorVersion, os.minorVersion, os.patchVersion) {
            case (9, 0, _):
                // "iOS >= 9.0.0, < 9.1.0"
                // Only in iOS 9.0.x, the contentInset of the collection view does not automatically add the statusbar height and the navigation bar height
                let statusBarheight = UIApplication.sharedApplication().statusBarFrame.height
                let navigationBarHeight = self.navigationController?.navigationBar.frame.height ?? 0
                self.constants.defaultContentInsets.top += statusBarheight + navigationBarHeight
                break
            default:
                // "iOS < 9.0.0 or >= 9.1.0"
                break
            }
        #endif