So I just came across this error while I was trying to integrate google sign in into one of my Flutter app.

shrinker may have failed to optimize the Java bytecode.
To disable the shrinker, pass the ` — no-shrink` flag to this command

So, to solve this error just navigate to {your-app-name}\android\app\build.gradle, when you get to the build.gradle file just scroll down to where defaultConfig was specified and change the minSdkVersion from 16 to 21 and the problem is gone.

This solution work like a charm, if your error has been solved through this article don’t forget subscribe to newsletter. Thanks

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