Export tombstones by default for debuggable VMs

VM config's export_tombstones is now optional. Default is true for
debuggable VMs, false for non-debuggable VMs.

Bug: 250165198
Test: atest MicrodroidHostTestCases
Change-Id: I818bcf3446b5bf7f560487265d82cd08f97c277e
diff --git a/tests/testapk/Android.bp b/tests/testapk/Android.bp
index 5f9b915..d8f0e11 100644
--- a/tests/testapk/Android.bp
+++ b/tests/testapk/Android.bp
@@ -26,6 +26,7 @@
         "MicrodroidEmptyNativeLib",
         "MicrodroidExitNativeLib",
         "MicrodroidPrivateLinkingNativeLib",
+        "MicrodroidCrashNativeLib",
     ],
     jni_uses_platform_apis: true,
     use_embedded_native_libs: true,
@@ -92,3 +93,11 @@
     shared_libs: ["libselinux#latest"],
     stl: "libc++_static",
 }
+
+// A payload that crashes immediately on start
+cc_library_shared {
+    name: "MicrodroidCrashNativeLib",
+    srcs: ["src/native/crashbinary.cpp"],
+    header_libs: ["vm_payload_headers"],
+    stl: "libc++_static",
+}