android-Error：任务'：app：processDebugGoogleServices'的执行失败。 ＆GT;文件google-services.json缺失

Question

我是android developnment的新手。我正在尝试在我的应用程序中集成firebase云消息通知服务。根据https://firebase.google.com/中提到的指南，我在我的应用程序文件夹中添加了google-services.json文件，但我仍然收到此错误说“文件google-services .json缺少模块根...“。请帮帮我。 下面是我的Build.gradle（项目级别）文件： -

buildscript {
repositories {
    jcenter()
}
dependencies {
    classpath 'com.android.tools.build:gradle:2.2.3'
    classpath 'com.google.gms:google-services:3.0.0'
    // NOTE: Do not place your application dependencies here; they belong
    // in the individual module build.gradle files
}
}

allprojects {
repositories {
    jcenter()
}
}

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

Build.gradle（应用级别）： -

 apply plugin: 'com.android.application'

 android {
 compileSdkVersion 25
 buildToolsVersion "25.0.0"
 defaultConfig {
    applicationId "mohit.munjal.firebasenotifications"
    minSdkVersion 15
    targetSdkVersion 25
    versionCode 1
    versionName "1.0"
    testInstrumentationRunner 
 "android.support.test.runner.AndroidJUnitRunner"
 }
 buildTypes {
    release {
        minifyEnabled false
        proguardFiles getDefaultProguardFile('proguard-android.txt'), 
   'proguard-rules.pro'
    }
 }
 }

 dependencies {
 compile 'com.google.android.gms:play-services:10.2.6'

 compile 'com.google.firebase:firebase-messaging:10.2.6'
 compile fileTree(dir: 'libs', include: ['*.jar'])
 androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', 
 {
    exclude group: 'com.android.support', module: 'support-annotations'
 })
 compile 'com.android.support:appcompat-v7:25.3.1'
 testCompile 'junit:junit:4.12'
}
apply plugin: 'com.google.gms.google-services'

错误： -

Error:Execution failed for task ':app:processDebugGoogleServices'.> File 
google-services.json is missing. The Google Services Plugin cannot 
function without it. 
Searched Location: 
D:\Android studio projects\FirebaseCloudMessagingApp\app\src\debug\google-
services.json
D:\Android studio projects\FirebaseCloudMessagingApp\app\google-
services.json