After upgrading to Android Studio 3.0, many configs changed.
Please check https://developer.android.com/studio/build/gradle-plugin-3-0-0-migration.html for details.

Versions

Android Studio as an IDE often breaks because of the incompatibility of these three components:

• Android Studio
• Gradle
• Android Plugin for Gradle

Make sure they are compatible.

In latest version as 2018/02/23,

• Android Studio v3.0.1
• Gradle v4.1
• Android Plugin for Gradle v3.0.1

The version for Android Studio and Android Plugin for Gradle should be always the same.

Naming

com.android.feature

implementation, api, compileOnly, and runtimeOnly.

flavor dimensions