3435 [camera] combine release messages and versions (cla: yes, waiting for tree to go green)

3437 [plugin_platform_interface] Use Mockito nnbd (cla: yes, waiting for tree to go green)

3444 [camera] Ensure that channel.invokeMethod runs on the main thread (cla: yes, p: camera, waiting for tree to go green)

3449 [google_maps_flutter_platform_interface] Fixes for custom tiles (cla: yes, p: google_maps_flutter, waiting for tree to go green)

waiting for test harness - 6 pull request(s)

3070 [path_provider_android] Move Path operations to background thread (cla: yes, waiting for test harness)

3116 [integration_test] Add watchPerformance (cla: yes, waiting for test harness)