Merge branch 'master' into android-p-support

.cirrus.yml

-task:
-  container:
-    dockerfile: .ci/Dockerfile
-    cpu: 8
-    memory: 16G
-  pub_cache:
-    folder: ~/.pub-cache
-  setup_script:
-    - flutter channel stable
-    - flutter upgrade
-  build_script:
-    - cd example
-    - flutter build apk
-  #test_script: flutter test
-
-task:
-  osx_instance:
-    image: catalina-xcode-11.3.1-flutter
-  pub_cache:
-    folder: ~/.pub-cache
-  setup_script:
-    - pod repo update
-    - flutter channel stable
-    - flutter upgrade
-  create_simulator_script:
-    - xcrun simctl list
-    - xcrun simctl create Flutter-iPhone com.apple.CoreSimulator.SimDeviceType.iPhone-X com.apple.CoreSimulator.SimRuntime.iOS-13-3 | xargs xcrun simctl boot
-  build_script:
-    - cd example
-    - flutter build ios --no-codesign
-  #test_script: flutter test