Flutter v1.1.0

• Add customization on CheckoutParams: an optional AndroidBrowserOptions/
  IosBrowserOptions pair. Android covers toolbar and
  navigation-bar(-divider) colors, close button style and position,
  share/title/URL-bar-hiding/bookmarks/downloads toggles, and a forced
  light/dark color scheme. iOS covers dismiss button style, bar-collapsing,
  presentation style, and color scheme. Every field is nullable and simply
  transmitted as null when unset, so the underlying platform's own current
  behavior applies rather than this SDK asserting a value on its behalf.
• Bumps com.dodopayments.api:checkout-android to 1.1.0 and re-vendors the
  Swift core with the same customization support.