build.gradle

// Top-level build file where you can add configuration options common to all sub-projects/modules.

buildscript {
    repositories {
        google()
        jcenter()
        mavenCentral()
        maven {
            url 'https://maven.fabric.io/public'
        }
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:3.1.3'
        classpath 'io.fabric.tools:gradle:1.25.4'
        classpath 'com.google.gms:google-services:3.2.1'
        classpath 'com.google.firebase:firebase-plugins:1.1.5'
        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files

    }
}

allprojects {
    repositories {
        jcenter()
        google()
        maven {
            url "https://jitpack.io"
        }
        repositories {
            // ...
            maven {
                url "https://maven.google.com" // Google's Maven repository
            }
        }
    }
}

task clean(type: Delete) {
    delete rootProject.buildDir
}