Summary:
This PR bumps gradle to 5.0, which includes Kotlin DSL 1.0, and android gradle plugin to 3.3.1, which includes includes various bug fixes and performance improvements. Also Gradle 5.x requires Java 8.
This is preparation for Kotlin DSL migration.
[Android] [Changed] - Bump Gradle to 5.0
Pull Request resolved: https://github.com/facebook/react-native/pull/23324
Reviewed By: mdvacca
Differential Revision: D14028563
Pulled By: hramos
fbshipit-source-id: 61fe1a2d4ea5707d6f07945acbd950f852420e13