push.gradle

import java.util.regex.Pattern

def doExtractStringFromManifest(name) {
    def manifestFile = file(android.sourceSets.main.manifest.srcFile)
    def pattern = Pattern.compile(name + "=\"(.*?)\"")
    def matcher = pattern.matcher(manifestFile.getText())
    matcher.find()
    return matcher.group(1)
}

android {
    sourceSets {
        main {
            manifest.srcFile 'AndroidManifest.xml'
        }
    }

    defaultConfig {
        multiDexEnabled true
        applicationId = doExtractStringFromManifest("package")
    }
}

buildscript {
	repositories {
      jcenter()
			mavenLocal()
  }
  dependencies {
      classpath 'com.android.tools.build:gradle:+'
      classpath 'com.google.gms:google-services:3.0.0'
  }
}

// apply plugin: 'com.google.gms.google-services'
// class must be used instead of id(string) to be able to apply plugin from non-root gradle file
ext.postBuildExtras = {
    apply plugin: com.google.gms.googleservices.GoogleServicesPlugin
}