2017.4构建googlevr sdk源项目hellovr安卓输出时，提示错误。（不发布vr项目时，可以正常构建安卓apk）

CommandInvokationFailure: Gradle build failed. 
D:/jdk1.8\bin\java.exe -classpath "C:\Program Files\Unity\Hub\Editor\2017.4.21f1\Editor\Data\PlaybackEngines\AndroidPlayer\Tools\gradle\lib\gradle-launcher-4.6.jar" org.gradle.launcher.GradleMain "-Dorg.gradle.jvmargs=-Xmx4096m" "assembleRelease"

stderr[
java.io.IOException: java.util.concurrent.ExecutionException: java.io.UncheckedIOException: java.nio.file.FileSystemException: D:\AndroidDevTools\android-sdk-windows\.android\build-cache\3.2.0\3f02bbee40105c0634ecea4069ca38c1cf66131aad066d080f4ae4cea2e4ec07.lock: ���̿ռ䲻�㡣

Build completed with a result of 'Failed'
UnityEngine.GUIUtility:ProcessEvent(Int32, IntPtr)

UnityEditor.BuildPlayerWindow+BuildMethodException: 2 errors
  at UnityEditor.BuildPlayerWindow+DefaultBuildMethods.BuildPlayer (BuildPlayerOptions options) [0x0020e] in D:\unity\Editor\Mono\BuildPlayerWindowBuildMethods.cs:181 
  at UnityEditor.BuildPlayerWindow.CallBuildMethods (Boolean askForBuildLocation, BuildOptions defaultBuildOptions) [0x00065] in D:\unity\Editor\Mono\BuildPlayerWindowBuildMethods.cs:88 
UnityEngine.GUIUtility:ProcessEvent(Int32, IntPtr)