Fix broken build

Author: vancexu

build.gradle

@@ -1,7 +1,7 @@
 plugins {
     id 'net.minecrell.licenser' version '0.3'
     id "com.github.sherter.google-java-format" version "0.6"
-    id "net.ltgt.errorprone" version "0.0.13"
+    id "net.ltgt.errorprone" version "0.6"
 }
 
 apply plugin: 'java'
@@ -33,6 +33,8 @@ repositories {
 }
 
 dependencies {
+    errorproneJavac("com.google.errorprone:javac:9+181-r4173-1")
+    errorprone("com.google.errorprone:error_prone_core:2.3.1")
     compile group: 'com.uber.cadence', name: 'cadence-client', version: '2.5.2'
     compile group: 'commons-configuration', name: 'commons-configuration', version: '1.9'
     compile group: 'ch.qos.logback', name: 'logback-classic', version: '1.2.3'
@@ -44,8 +46,8 @@ dependencies {
 compileJava {
     dependsOn 'googleJavaFormat'
     options.encoding = 'UTF-8'
-    options.compilerArgs << "-Xlint:unchecked" << "-Xlint:deprecation" << "-XepExcludedPaths:" +
-            ".*/generated-sources/.*"
+    options.compilerArgs << "-Xlint:unchecked" << "-Xlint:deprecation"
+    options.errorprone.errorproneArgs << "-XepExcludedPaths:.*/generated-sources/.*"
 }
 
 task execute(type: JavaExec) {

gradle/wrapper/gradle-wrapper.jar

@@ -1,6 +1,5 @@
-#Sun Feb 25 06:11:50 GMT 2018
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-4.6-bin.zip
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-4.5.1-all.zip

gradle/wrapper/gradle-wrapper.properties

@@ -1,3 +1,20 @@
+/*
+ *  Copyright 2012-2016 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ *
+ *  Modifications copyright (C) 2017 Uber Technologies, Inc.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License"). You may not
+ *  use this file except in compliance with the License. A copy of the License is
+ *  located at
+ *
+ *  http://aws.amazon.com/apache2.0
+ *
+ *  or in the "license" file accompanying this file. This file is distributed on
+ *  an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
+ *  express or implied. See the License for the specific language governing
+ *  permissions and limitations under the License.
+ */
+
 package com.uber.cadence.samples.hello;
 
 import static com.uber.cadence.samples.common.SampleConstants.DOMAIN;