ART: Remove test files after test

The unix_file tests should remove files and directories when they
are done testing.

Bug: 16505797

(cherry picked from commit 7747c8de402f64e3009ca3bcccebddbb70f617ee)

Change-Id: I9c3c8f1a80ec0d37628a742193267e182c25b0cd
diff --git a/runtime/common_runtime_test.h b/runtime/common_runtime_test.h
index eb96352..9ceb551 100644
--- a/runtime/common_runtime_test.h
+++ b/runtime/common_runtime_test.h
@@ -64,7 +64,13 @@
 
 class CommonRuntimeTest : public testing::Test {
  public:
-  static void SetEnvironmentVariables(std::string& android_data);
+  static void SetUpAndroidRoot();
+
+  // Note: setting up ANDROID_DATA may create a temporary directory. If this is used in a
+  // non-derived class, be sure to also call the corresponding tear-down below.
+  static void SetUpAndroidData(std::string& android_data);
+
+  static void TearDownAndroidData(const std::string& android_data, bool fail_on_error);
 
   CommonRuntimeTest();
   ~CommonRuntimeTest();