Don't run testTombstonesAreBeingForwarded on user builds

The test requires rooting which is impossible on user builds.

Ignore-AOSP-First: will cherry-pick to AOSP

Bug: 222013014
Test: atest MicrodroidHostTestCases on user build
Change-Id: I422167ed1f43ab568e4a2676f6c3709b6df2017d
diff --git a/tests/hostside/java/android/virt/test/MicrodroidTestCase.java b/tests/hostside/java/android/virt/test/MicrodroidTestCase.java
index 32bdf3b..67f48a3 100644
--- a/tests/hostside/java/android/virt/test/MicrodroidTestCase.java
+++ b/tests/hostside/java/android/virt/test/MicrodroidTestCase.java
@@ -361,6 +361,10 @@
 
     @Test
     public void testTombstonesAreBeingForwarded() throws Exception {
+        // This test requires rooting. Skip on user builds where rooting is impossible.
+        final String buildType = getDevice().getProperty("ro.build.type");
+        assumeTrue("userdebug".equals(buildType) || "eng".equals(buildType));
+
         // Note this test relies on logcat values being printed by tombstone_transmit on
         // and the reeceiver on host (virtualization_service)
         final String configPath = "assets/vm_config.json"; // path inside the APK