Android gradle build：在APK LICENSE.txt打包期间重复文件

buildscript {
    repositories {
        mavenCentral()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:0.4.2'
    }

apply plugin: 'android-library'

repositories {
  mavenCentral()
}

dependencies {
    instrumentTESTCompile "junit:junit:4.+"        
}

android {
    compileSdkVersion 17
    buildToolsVersion "17.0.0"

    instrumentTest.setRoot('tests')
    instrumentTest {
      java.srcDirs = ['tests/src']
      res.srcDirs = ['tests/res']
      assets.srcDirs = ['tests/assets']
      resources.srcDirs = ['tests/src']
        }        
    }
}

运行时我收到以下错误：