[vm/ffi] Call natives through stubs if write-protection is enabled without dual-mapping.

Addresses the Dart -> Native half of dartbug.com/37629

Change-Id: I242b7f3a14dd105334a8b6e5c089b173c398491e
Cq-Include-Trybots: luci.dart.try:vm-ffi-android-debug-arm-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/111280
Commit-Queue: Samir Jindel <sjindel@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>

tests/ffi/function_gc_test.dart

@@ -4,6 +4,8 @@
 //
 // VMOptions=--deterministic --optimization-counter-threshold=500 --enable-testing-pragmas
 // VMOptions=--deterministic --optimization-counter-threshold=-1 --enable-testing-pragmas
+// VMOptions=--deterministic --optimization-counter-threshold=500 --enable-testing-pragmas --no-dual-map-code --write-protect-code
+// VMOptions=--deterministic --optimization-counter-threshold=-1 --enable-testing-pragmas --no-dual-map-code --write-protect-code
 //
 // Dart test program for stress-testing boxing and GC in return paths from FFI
 // trampolines.
@@ -25,6 +27,7 @@ main() async {
   testBoxPointer();
   testAllocateInNative();
   testRegress37069();
+  testWriteProtection();
 }
 
 typedef NativeNullaryOp64 = ffi.Int64 Function();
@@ -106,3 +109,11 @@ final regress37069 = ffiTestFunctions
 void testRegress37069() {
   regress37069(1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11);
 }
+
+final unprotectCode = ffiTestFunctions
+    .lookupFunction<NativeNullaryOp32, NullaryOp>("UnprotectCode");
+
+void testWriteProtection() {
+  int result = unprotectCode();
+  Expect.equals(result, 0);
+}

tests/ffi/function_test.dart

@@ -7,6 +7,8 @@
 // VMOptions=
 // VMOptions=--deterministic --optimization-counter-threshold=10
 // VMOptions=--use-slow-path
+// VMOptions=--write-protect-code --no-dual-map-code
+// VMOptions=--write-protect-code --no-dual-map-code --use-slow-path
 // SharedObjects=ffi_test_functions
 
 library FfiTest;