Wait for Android plugin to load before configuring plugin dependency

[blasten]

implementation is provided by the Android Gradle plugin. It cannot be called before the Android plugin has loaded, and registered an implementation callback.

afterEvaluate ensures that implementation is only called after this plugin loaded.

[xster]

LGTM. Can we add a test?

[blasten]

@xster test added

[fluttergithubbot]

This pull request is not suitable for automatic merging in its current state.

• Please get at least one approved review before re-applying this label. Reviewers: If you left a comment approving, please use the "approve" review action instead.
• The status or check suite Mac build_tests has failed. Please fix the issues identified (or deflake) before re-applying this label.

[jonahwilliams]

This should not be running in the devicelab since it does not require dedicated hardware.

[blasten]

I discussed adding this to LUCI with @godofredoc. Currently, it's a manual process, and cannot be done in a single PR like this one.

This would have to be done after the holidays most likely.

[jonahwilliams]

I filled #70978 to track. Its not so urgent that we need to deal with it right now

[blasten]

Thanks @jonahwilliams ! I know @godofredoc is on top of improving this devX.