Android Studio not recognizes Espresso imports
<p>I am trying to write a test case using Espresso.</p>

<p>I am using Android Studio 1.5.1 (Stable channel), Gradle plugin 1.5, Gradle 2.7.
The problem is that Android Studio doesn't recognize any import related to Espresso (and not only)<a href="https://i.stack.imgur.com/llFaJ.png"><img src="https://i.stack.imgur.com/llFaJ.png" alt="enter image description here"></a></p>

<p>So, I tried to clean the project, rebuild, invalidate cache and restart, but nothing.</p>

<p>I added these dependencies in my app module:</p>

<pre><code>androidTestCompile 'com.android.support.test.espresso:espresso-core:2.2.1'
androidTestCompile 'com.android.support:support-annotations:23.1.1'
androidTestCompile 'com.android.support.test:runner:0.4.1'
androidTestCompile 'com.android.support.test:rules:0.4.1'
</code></pre>

<p>I added the runner in defaultConfig:</p>

<pre><code>testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
</code></pre>

<p>I created the test suite class under androidTest folder:</p>

<p><a href="https://i.stack.imgur.com/oBMrS.png"><img src="https://i.stack.imgur.com/oBMrS.png" alt="enter image description here"></a></p>

<p>What am I doing wrong please?</p>

<p><strong>UPDATE</strong></p>

<p>Here is (part) of my build.gradle:</p>

<pre><code>apply plugin: 'com.android.application'
apply plugin: 'com.neenbedankt.android-apt'

android {
    compileSdkVersion 23
    buildToolsVersion '23.0.2'

    defaultConfig {
        minSdkVersion 15
        targetSdkVersion 23
        versionCode 5
        versionName '1.4'

        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
    }

    compileOptions {
        sourceCompatibility JavaVersion.VERSION_1_7
        targetCompatibility JavaVersion.VERSION_1_7
    }

    buildTypes {
        //my build type configs
    }

    packagingOptions {
        exclude 'META-INF/services/javax.annotation.processing.Processor'
        exclude 'META-INF/LICENSE'
        exclude 'META-INF/LICENSE.txt'
        exclude 'META-INF/NOTICE'
        exclude 'META-INF/NOTICE.txt'
    }

    lintOptions {
        disable 'InvalidPackage'
    }

    dexOptions {
        incremental true
        preDexLibraries = false
        jumboMode = false
        javaMaxHeapSize "2g"
    }
}

dependencies {
    compile fileTree(include: ['*.jar'], dir: 'libs')
    compile 'com.viewpagerindicator:library:2.4.1'
    compile project(':libraries:RITracking')
    compile 'com.android.support:support-v4:23.1.1'
    compile 'com.android.support:design:23.1.1'
    compile 'com.android.support:support-annotations:23.1.1'
    compile 'com.android.support:recyclerview-v7:23.1.1'
    compile 'com.android.support:cardview-v7:23.1.1'
    compile 'com.android.support:gridlayout-v7:23.1.1'
    compile 'com.google.code.gson:gson:2.5'
    compile 'com.google.android.gms:play-services-plus:8.4.0'
    compile 'com.google.android.gms:play-services-base:8.4.0'
    compile 'de.greenrobot:eventbus:2.4.1'
    compile 'com.squareup.retrofit:retrofit:1.9.0'
    compile 'com.squareup.okhttp:okhttp:2.7.2'
    compile 'com.facebook.android:facebook-android-sdk:4.9.0'
    compile 'com.cocosw:bottomsheet:1.2.0@aar'                          //Bottom Sheet that implement material design used for ShareDialog
    compile 'com.github.bumptech.glide:glide:3.6.1'                     //Glide library
    compile 'com.googlecode.libphonenumber:libphonenumber:7.2.3'        //Library used to parse/merge phones number to E164 format
    compile 'me.leolin:ShortcutBadger:1.1.3@aar'                        //Used to show badge on application icon, library is optimized to work on most of devices
    compile 'com.stripe:stripe-android:1.0.3'                              //Stripe payment gateway, used to integrate credit card payment
    provided 'org.projectlombok:lombok:1.16.6'
    apt "org.projectlombok:lombok:1.16.6"
    compile 'com.jakewharton:butterknife:7.0.1'
    apt "com.jakewharton:butterknife:7.0.1"
    compile 'de.greenrobot:greendao:2.1.0'                              //Green Dao library is ORM implementation for Android SQL lite
    compile files('libs/libammsdk.jar')
    compile files('libs/apptimize-android-2.9.1.jar')

    testCompile 'junit:junit:4.12'

    androidTestCompile "com.android.support:support-annotations:23.1.1"
    androidTestCompile 'com.android.support.test.espresso:espresso-core:2.2.1'
    androidTestCompile 'com.android.support.test.espresso:espresso-intents:2.2.1'
    androidTestCompile('com.android.support.test.espresso:espresso-contrib:2.2.1') {
        exclude group: 'com.android.support', module: 'appcompat'
        exclude group: 'com.android.support', module: 'support-v4'
        exclude module: 'recyclerview-v7'
    }
    androidTestCompile 'com.android.support.test:runner:0.4.1'
    androidTestCompile 'com.android.support.test:rules:0.4.1'
}
</code></pre>