message: delete view controller ref
diff: import { Box, color, Flex, Sans, space, Spacer } from "@artsy/palette"
  import { Schema } from "lib/utils/track"
  import { useScreenDimensions } from "lib/utils/useScreenDimensions"
  -import React, { useRef, useState } from "react"
  +import React, { useState } from "react"
  import { NativeModules, TouchableOpacity, View } from "react-native"
  import Animated from "react-native-reanimated"
  import { useTracking } from "react-tracking"
  @@ -35,7 +35,6 @@ export const StickyTabPage: React.FC<{
  const [headerHeight, setHeaderHeight] = useState<null | number>(null)
  const tracking = useTracking()
  const headerOffsetY = useAnimatedValue(0)
  - const viewControllerRef = useRef(null)
  const shouldHideBackButton = Animated.lessOrEq(headerOffsetY, -10)
  @@ -44,9 +43,7 @@ export const StickyTabPage: React.FC<{
  Animated.onChange(
  shouldHideBackButton,
  Animated.call([shouldHideBackButton], ([shouldHide]) => {
  - if (viewControllerRef.current) {
  ARSwitchBoardModule.updateShouldHideBackButton(shouldHide)
  - }
  })
  ),
  []
  @@ -61,7 +58,7 @@ export const StickyTabPage: React.FC<{
  }
  return (
  - <View style={{ flex: 1, position: "relative", overflow: "hidden" }} ref={viewControllerRef}>
  + <View style={{ flex: 1, position: "relative", overflow: "hidden" }}>
  {/* put tab content first because we want the header to be absolutely positioned _above_ it */}
  {headerHeight !== null && (
  <SnappyHorizontalRail offset={activeTabIndex * width}>
  