cppgc: Don't override stack_state in unified heap GC finalization.

CppHeap is currently set up to always finalize with no stack.
Finalizing with actual current stack state breaks our unified heap
unittests. This is fixed by having test specify which stack state
to pass CppHeap.

Bug: chromium:1056170
Change-Id: I1a6c3870abbdf56917c20c6a75580b6c516d828c
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2494924
Commit-Queue: Omer Katz <omerkatz@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#70729}

src/heap/cppgc-js/cpp-heap.cc

@@ -194,7 +194,7 @@ bool CppHeap::AdvanceTracing(double deadline_in_ms) {
 bool CppHeap::IsTracingDone() { return marking_done_; }
 
 void CppHeap::EnterFinalPause(EmbedderStackState stack_state) {
-  marker_->EnterAtomicPause(cppgc::Heap::StackState::kNoHeapPointers);
+  marker_->EnterAtomicPause(stack_state);
 }
 
 void CppHeap::TraceEpilogue(TraceSummary* trace_summary) {

src/heap/heap.h

@@ -1127,7 +1127,7 @@ class Heap {
   EmbedderHeapTracer* GetEmbedderHeapTracer() const;
 
   void RegisterExternallyReferencedObject(Address* location);
-  void SetEmbedderStackStateForNextFinalizaton(
+  V8_EXPORT_PRIVATE void SetEmbedderStackStateForNextFinalizaton(
       EmbedderHeapTracer::EmbedderStackState stack_state);
 
   EmbedderHeapTracer::TraceFlags flags_for_embedder_tracer() const;

test/unittests/heap/unified-heap-unittest.cc

@@ -56,6 +56,18 @@ class UnifiedHeapTest : public TestWithHeapInternals {
     cppgc::ShutdownProcess();
   }
 
+  void CollectGarbageWithEmbedderStack() {
+    heap()->SetEmbedderStackStateForNextFinalizaton(
+        EmbedderHeapTracer::EmbedderStackState::kMayContainHeapPointers);
+    CollectGarbage(OLD_SPACE);
+  }
+
+  void CollectGarbageWithoutEmbedderStack() {
+    heap()->SetEmbedderStackStateForNextFinalizaton(
+        EmbedderHeapTracer::EmbedderStackState::kNoHeapPointers);
+    CollectGarbage(OLD_SPACE);
+  }
+
   CppHeap& cpp_heap() const { return *cpp_heap_.get(); }
 
   cppgc::AllocationHandle& allocation_handle() {
@@ -80,7 +92,7 @@ size_t Wrappable::destructor_callcount = 0;
 
 }  // namespace
 
-TEST_F(UnifiedHeapTest, OnlyGC) { CollectGarbage(OLD_SPACE); }
+TEST_F(UnifiedHeapTest, OnlyGC) { CollectGarbageWithEmbedderStack(); }
 
 TEST_F(UnifiedHeapTest, FindingV8ToBlinkReference) {
   v8::HandleScope scope(v8_isolate());
@@ -90,12 +102,12 @@ TEST_F(UnifiedHeapTest, FindingV8ToBlinkReference) {
       context, cppgc::MakeGarbageCollected<Wrappable>(allocation_handle()));
   EXPECT_FALSE(api_object.IsEmpty());
   EXPECT_EQ(0u, Wrappable::destructor_callcount);
-  CollectGarbage(OLD_SPACE);
+  CollectGarbageWithoutEmbedderStack();
   EXPECT_EQ(0u, Wrappable::destructor_callcount);
   ResetWrappableConnection(api_object);
-  CollectGarbage(OLD_SPACE);
+  CollectGarbageWithoutEmbedderStack();
   // Calling CollectGarbage twice to force the first GC to finish sweeping.
-  CollectGarbage(OLD_SPACE);
+  CollectGarbageWithoutEmbedderStack();
   EXPECT_EQ(1u, Wrappable::destructor_callcount);
 }