java.lang.ClassCastException: java.lang.NoClassDefFoundError cannot be cast to java.lang.RuntimeException

Activity activity = Robolectric.setupActivity(MainActivity.class);

buildscript {
    repositories {
        mavenCentral()
        jcenter()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:1.0.0'
        classpath 'com.github.jcandksolutions.gradle:android-unit-test:2.1.1'

        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}

allprojects {
    repositories {
        jcenter()
    }
}

apply plugin: 'com.android.application'

repositories {
    mavenCentral()
}

android {
    compileSdkVersion 21
    buildToolsVersion "21.1.2"

    defaultConfig {
        applicationId "com.example.robolectrictest"
        minSdkVersion 15
        targetSdkVersion 21
        versionCode 1
        versionName "1.0"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }

    sourceSets {
        main {
            jniLibs.srcDirs = ['libs']
        }

        androidTest {
            setRoot('src/androidTest')
        }
    }
}

// Must be after Android plugin
apply plugin: 'android-unit-test'

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    compile 'com.android.support:appcompat-v7:21.0.3'

    //androidTestCompile 'junit:junit:4.10'
    //androidTestCompile 'org.robolectric:robolectric:2.4'

    // Testing frameworks
    testCompile 'junit:junit:4.10'
    testCompile 'org.robolectric:robolectric:2.4'
}

public class MainActivity extends ActionBarActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }


    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.menu_main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();

        //noinspection SimplifiableIfStatement
        if (id == R.id.action_settings) {
            return true;
        }

        return super.onOptionsItemSelected(item);
    }
}

@Config(emulateSdk = 18)
@RunWith(RobolectricTestRunner.class)

public class ApplicationTest {

    @org.junit.Test
    public void testDummy() throws Exception {

        Activity activity = Robolectric.setupActivity(MainActivity.class);

        assertTrue(true);
    }

}