Revert "Background finalization."

runtime/vm/dart_api_impl_test.cc

Index: runtime/vm/dart_api_impl_test.cc
diff --git a/runtime/vm/dart_api_impl_test.cc b/runtime/vm/dart_api_impl_test.cc
index 2ab0656d87bdd4e945aa0c0591eb3f8dbac725df..fcc4e79cd8cc88cc39f412f13ed1490c827bd007 100644
--- a/runtime/vm/dart_api_impl_test.cc
+++ b/runtime/vm/dart_api_impl_test.cc
@@ -1206,28 +1206,6 @@ TEST_CASE(MalformedStringToUTF8) {
 }
 
 
-// Helper class to ensure new gen GC is triggered without any side effects.
-// The normal call to CollectGarbage(Heap::kNew) could potentially trigger
-// an old gen collection if there is a promotion failure and this could
-// perturb the test.
-class GCTestHelper : public AllStatic {
- public:
-  static void CollectNewSpace(Heap::ApiCallbacks api_callbacks) {
-    bool invoke_api_callbacks = (api_callbacks == Heap::kInvokeApiCallbacks);
-    Isolate::Current()->heap()->new_space()->Scavenge(invoke_api_callbacks);
-  }
-
-  static void WaitForFinalizationTasks() {
-    Thread* thread = Thread::Current();
-    Heap* heap = thread->isolate()->heap();
-    MonitorLocker ml(heap->finalization_tasks_lock());
-    while (heap->finalization_tasks() > 0) {
-      ml.WaitWithSafepointCheck(thread);
-    }
-  }
-};
-
-
 static void ExternalStringCallbackFinalizer(void* peer) {
   *static_cast<int*>(peer) *= 2;
 }
@@ -1264,11 +1242,9 @@ TEST_CASE(ExternalStringCallback) {
     EXPECT_EQ(40, peer8);
     EXPECT_EQ(41, peer16);
     Isolate::Current()->heap()->CollectGarbage(Heap::kOld);
-    GCTestHelper::WaitForFinalizationTasks();
     EXPECT_EQ(40, peer8);
     EXPECT_EQ(41, peer16);
     Isolate::Current()->heap()->CollectGarbage(Heap::kNew);
-    GCTestHelper::WaitForFinalizationTasks();
     EXPECT_EQ(80, peer8);
     EXPECT_EQ(82, peer16);
   }
@@ -2405,10 +2381,8 @@ TEST_CASE(ExternalTypedDataCallback) {
     TransitionNativeToVM transition(thread);
     EXPECT(peer == 0);
     Isolate::Current()->heap()->CollectGarbage(Heap::kOld);
-    GCTestHelper::WaitForFinalizationTasks();
     EXPECT(peer == 0);
     Isolate::Current()->heap()->CollectGarbage(Heap::kNew);
-    GCTestHelper::WaitForFinalizationTasks();
     EXPECT(peer == 42);
   }
 }
@@ -2465,7 +2439,6 @@ TEST_CASE(Float32x4List) {
   {
     TransitionNativeToVM transition(thread);
     Isolate::Current()->heap()->CollectGarbage(Heap::kNew);
-    GCTestHelper::WaitForFinalizationTasks();
     EXPECT(peer == 42);
   }
 }
@@ -2628,6 +2601,19 @@ UNIT_TEST_CASE(AssignToPersistentHandle) {
 }
 
 
+// Helper class to ensure new gen GC is triggered without any side effects.
+// The normal call to CollectGarbage(Heap::kNew) could potentially trigger
+// an old gen collection if there is a promotion failure and this could
+// perturb the test.
+class GCTestHelper : public AllStatic {
+ public:
+  static void CollectNewSpace(Heap::ApiCallbacks api_callbacks) {
+    bool invoke_api_callbacks = (api_callbacks == Heap::kInvokeApiCallbacks);
+    Isolate::Current()->heap()->new_space()->Scavenge(invoke_api_callbacks);
+  }
+};
+
+
 static Dart_Handle AsHandle(Dart_PersistentHandle weak) {
   return Dart_HandleFromPersistent(weak);
 }
@@ -2742,7 +2728,6 @@ TEST_CASE(WeakPersistentHandle) {
     TransitionNativeToVM transition(thread);
     // Garbage collect new space again.
     GCTestHelper::CollectNewSpace(Heap::kIgnoreApiCallbacks);
-    GCTestHelper::WaitForFinalizationTasks();
   }
 
   {
@@ -2758,7 +2743,6 @@ TEST_CASE(WeakPersistentHandle) {
     TransitionNativeToVM transition(thread);
     // Garbage collect old space again.
     Isolate::Current()->heap()->CollectGarbage(Heap::kOld);
-    GCTestHelper::WaitForFinalizationTasks();
   }
 
   {
@@ -2803,7 +2787,6 @@ TEST_CASE(WeakPersistentHandleCallback) {
     Isolate::Current()->heap()->CollectGarbage(Heap::kOld);
     EXPECT(peer == 0);
     GCTestHelper::CollectNewSpace(Heap::kIgnoreApiCallbacks);
-    GCTestHelper::WaitForFinalizationTasks();
     EXPECT(peer == 42);
   }
 }
@@ -2830,7 +2813,6 @@ TEST_CASE(WeakPersistentHandleNoCallback) {
     Isolate::Current()->heap()->CollectGarbage(Heap::kOld);
     EXPECT(peer == 0);
     GCTestHelper::CollectNewSpace(Heap::kIgnoreApiCallbacks);
-    GCTestHelper::WaitForFinalizationTasks();
     EXPECT(peer == 0);
   }
 }
@@ -2891,7 +2873,6 @@ TEST_CASE(WeakPersistentHandleExternalAllocationSize) {
     // Collect weakly referenced string, and promote strongly referenced string.
     GCTestHelper::CollectNewSpace(Heap::kIgnoreApiCallbacks);
     GCTestHelper::CollectNewSpace(Heap::kIgnoreApiCallbacks);
-    GCTestHelper::WaitForFinalizationTasks();
     EXPECT(heap->ExternalInWords(Heap::kNew) == 0);
     EXPECT(heap->ExternalInWords(Heap::kOld) == kWeak2ExternalSize / kWordSize);
   }
@@ -2902,7 +2883,6 @@ TEST_CASE(WeakPersistentHandleExternalAllocationSize) {
   {
     TransitionNativeToVM transition(thread);
     Isolate::Current()->heap()->CollectGarbage(Heap::kOld);
-    GCTestHelper::WaitForFinalizationTasks();
     EXPECT(heap->ExternalInWords(Heap::kOld) == 0);
   }
 }
@@ -2948,7 +2928,6 @@ TEST_CASE(WeakPersistentHandleExternalAllocationSizeNewspaceGC) {
   {
     TransitionNativeToVM transition(thread);
     Isolate::Current()->heap()->CollectGarbage(Heap::kOld);
-    GCTestHelper::WaitForFinalizationTasks();
     EXPECT(heap->ExternalInWords(Heap::kOld) == 0);
   }
 }