Q:

Android project update and how to solve: "Failed to resolve: monitor"? 

Because of problem that jcenter() remove some older libs I decide to update my project. 
So now I have:
 gradle: 4.6

and:
classpath 'com.android.tools.build:gradle:3.2.1'
classpath 'com.google.gms:google-services:3.0.0'

I almost solve every dependency but I get 
Failed to resolve: monitor

without any clue what is that monitor ;(

A:

Same for me.  It works If I comment espresso libraries and:

androidTestImplementation 'com.android.support.test:runner:1.0.2'
    androidTestImplementation 'com.android.support.test:rules:1.0.2'

I´ve found a solution.  Put google() at the beggining in

buildscript {
  repositories {
      google()

and 

allprojects {
    repositories {
      google()

in project gradlew

A:

On my project, when I remove the dependencies:
androidTestImplementation 'com.android.support.test:runner:1.0.2'
androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'

This error is gone. 
Good luck!