Elevation does not animate when it is inside a view which animates its opacity (Android P)

Environment

  React Native Environment Info:
    System:
      OS: macOS 10.14.1
      CPU: x64 Intel(R) Core(TM) i5-8259U CPU @ 2.30GHz
      Memory: 40.65 MB / 16.00 GB
      Shell: 5.6.2 - /usr/local/bin/zsh
    Binaries:
      Node: 10.11.0 - ~/.nvm/versions/node/v10.11.0/bin/node
      Yarn: 1.13.0 - ~/.nvm/versions/node/v10.11.0/bin/yarn
      npm: 6.5.0 - ~/.nvm/versions/node/v10.11.0/bin/npm
      Watchman: 4.9.0 - /usr/local/bin/watchman
    SDKs:
      iOS SDK:
        Platforms: iOS 11.4, macOS 10.13, tvOS 11.4, watchOS 4.3
      Android SDK:
        Build Tools: 23.0.1, 26.0.2, 26.0.3, 27.0.2, 27.0.3, 28.0.1, 28.0.2, 28.0.3
        API Levels: 22, 23, 24, 25, 26, 27, 28
    IDEs:
      Android Studio: 3.3 AI-182.5107.16.33.5199772
      Xcode: 9.4.1/9F2000 - /usr/bin/xcodebuild
    npmPackages:
      react: 16.6.3 => 16.6.3
      react-native: 0.59.0 => 0.59.0
    npmGlobalPackages:
      react-native-cli: 2.0.1

Description

What described in the title works in any Android but not on Android P. See the differences:

Android P:

Below Android P:

Reproducible Demo

https://snack.expo.io/@satya164/elevation-issue---android-p

This can affect libraries like react-navigation when a new screen comes in animating its opacity. See https://github.com/react-navigation/react-navigation/issues/5535.

Can be found here also https://github.com/ferrannp/react-native-elevation-animation-android-pie with react-native 0.59.X.

首先在 Android P 和 P 之前的 Android 版本上运行链接的 Expo Snack，然后比较包含视图更改 opacity 时的 elevation 动画。跟踪涉及 elevation 和 opacity 动画的 React Native Android 路径；当 Android P 与受支持的旧版本上的行为一致，且不会导致演示案例出现回归时，即视为完成。