Handle BoundFunctions in d8.test.verifySourcePositions

If a bound function is passed as argument to
d8.test.verifySourcePositions, unwrap the bound target function.

Bug: chromium:1186491
Change-Id: I619cb27d19166e2dc59f3fda1e2324598640b04a
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2778275
Auto-Submit: Patrick Thier <pthier@chromium.org>
Commit-Queue: Camillo Bruni <cbruni@chromium.org>
Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Cr-Commit-Position: refs/heads/master@{#73598}

src/d8/d8.cc

@@ -1823,8 +1823,17 @@ void Shell::TestVerifySourcePositions(
 
   i::Isolate* i_isolate = reinterpret_cast<i::Isolate*>(isolate);
   HandleScope handle_scope(isolate);
-  i::Handle<i::JSFunction> function =
-      i::Handle<i::JSFunction>::cast(Utils::OpenHandle(*arg_fun));
+
+  auto callable = i::Handle<i::JSFunctionOrBoundFunction>::cast(
+      Utils::OpenHandle(*arg_fun));
+  while (callable->IsJSBoundFunction()) {
+    auto bound_function = i::Handle<i::JSBoundFunction>::cast(callable);
+    auto bound_target = bound_function->bound_target_function();
+    callable =
+        handle(i::JSFunctionOrBoundFunction::cast(bound_target), i_isolate);
+  }
+
+  i::Handle<i::JSFunction> function = i::Handle<i::JSFunction>::cast(callable);
   if (!function->shared().HasBytecodeArray()) {
     Throw(isolate, "Function has no BytecodeArray attached.");
     return;