完整错误：
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2: Task failed with an exception.
-----------
* What went wrong:
Could not resolve all files for configuration ':releaseCompileClasspath'.
> Could not resolve io.flutter:flutter_embedding_release:1.0.0-5d8bf811b3072390933d69f3e289a4bb673636c4.
Required by:
project :
> Could not resolve io.flutter:flutter_embedding_release:1.0.0-5d8bf811b3072390933d69f3e289a4bb673636c4.
> Could not get resource 'https://jcenter.bintray.com/io/flutter/flutter_embedding_release/1.0.0-5d8bf811b3072390933d69f3e289a4bb673636c4/flutter_embedding_release-1.0.0-5d8bf811b3072390933d69f3e289a4bb673636c4.pom'.
> Could not GET 'https://jcenter.bintray.com/io/flutter/flutter_embedding_release/1.0.0-5d8bf811b3072390933d69f3e289a4bb673636c4/flutter_embedding_release-1.0.0-5d8bf811b3072390933d69f3e289a4bb673636c4.pom'. Received status code 500 from server: Internal Server Error
* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.
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解决方案
在项目级别的build.gradle添加
maven { url "http://download.flutter.io" }