title: './gradlew -Dtest.single=SimpleTest test' runs all tests I have
body: <p>My project is normal Android project created on <strong>Android Studio</strong>.</p>
  
  <p><img src="https://i.stack.imgur.com/1TAUB.png" alt="project structure"></p>
  
  <p>I googled a lot to run a single test(tests in SimpleTest, 1 test in this case), everyone say that I should do like </p>
  
  <pre><code>./gradlew -Dtest.single=SimpleTest test
  </code></pre>
  
  <p>in my root folder. </p>
  
  <p>or I did in my inner project folder</p>
  
  <pre><code>../gradlew -Dtest.single=SimpleTest test
  </code></pre>
  
  <p>I tried so many ways like this but it always run all tests I have.(11 tests in all Classes)</p>
  
  <p>Is there a problem on my build.gradle or is there a something I missing?</p>
  
  <p>Here is my <strong>build.gradle</strong> file.</p>
  
  <pre><code>buildscript {
      repositories {
          mavenCentral()
      }
      dependencies {
          classpath 'com.android.tools.build:gradle:0.6.+'
  
          classpath 'com.github.jcandksolutions.gradle:android-unit-test:1.0.+'
      }
  }
  
  apply plugin: 'android'
  
      repositories {
          mavenCentral()
      }
  
  android {
      compileSdkVersion 18
      buildToolsVersion "18.1.1"
  
      defaultConfig {
          minSdkVersion 10
          targetSdkVersion 18
          // I changed this for this question
          packageName "com.XXX.XXXX"
      }
  
      sourceSets {
          instrumentTest.setRoot('src/test')
      }
  }
  
  apply plugin: 'android-unit-test'
  
  dependencies {
      repositories {
          mavenCentral()
      }
      compile 'com.android.support:support-v4:18.0.+'
      compile 'com.android.support:appcompat-v7:+'
  
      compile 'com.google.code.gson:gson:2.2.4'
      compile group:'com.squareup.picasso', name:'picasso', version:'2.1.1'
      compile group:'com.squareup.okhttp', name:'okhttp', version:'1.2.1'
      compile group:'com.squareup', name:'otto', version:'1.3.4'
  
      compile group:'com.jakewharton', name:'butterknife', version:'3.0.0'
  
      compile group:'com.github.kevinsawicki', name:'http-request', version:'5.4.1'
  
      compile fileTree(dir: 'libs', include: '*.jar')
  
      testCompile 'junit:junit:4.10'
      testCompile 'org.robolectric:robolectric:2.2'
      testCompile 'com.squareup:fest-android:1.0.+'
  
      instrumentTestCompile 'junit:junit:4.10'
      instrumentTestCompile 'org.robolectric:robolectric:2.2'
      instrumentTestCompile 'com.squareup:fest-android:1.0.+'
  }
  
  tasks.withType(Compile) {
      options.encoding = "UTF-8"
  }
  
  tasks.withType(Test) {
      testLogging {
          events 'started', 'passed'
      }
  }
  </code></pre>