Run JS micro tasks in the appropriate context.

R=jochen@chromium.org
BUG=385349
LOG=Y

Review URL: https://codereview.chromium.org/332923003

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@21933 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/isolate.cc

@@ -2292,12 +2292,10 @@ void Isolate::EnqueueMicrotask(Handle<Object> microtask) {
 
 
 void Isolate::RunMicrotasks() {
-  // TODO(adamk): This ASSERT triggers in mjsunit tests which
-  // call the %RunMicrotasks runtime function. But it should
-  // never happen outside of tests, so it would be nice to
-  // uncomment it.
-  //
-  // ASSERT(handle_scope_implementer()->CallDepthIsZero());
+  // In some mjsunit tests %RunMicrotasks is called explicitly, violating
+  // this assertion.  Therefore we also check for --allow-natives-syntax.
+  ASSERT(FLAG_allow_natives_syntax ||
+         handle_scope_implementer()->CallDepthIsZero());
 
   // Increase call depth to prevent recursive callbacks.
   v8::Isolate::SuppressMicrotaskExecutionScope suppress(
@@ -2317,6 +2315,8 @@ void Isolate::RunMicrotasks() {
       if (microtask->IsJSFunction()) {
         Handle<JSFunction> microtask_function =
             Handle<JSFunction>::cast(microtask);
+        SaveContext save(this);
+        set_context(microtask_function->context()->native_context());
         Handle<Object> exception;
         MaybeHandle<Object> result = Execution::TryCall(
             microtask_function, factory()->undefined_value(),

test/cctest/test-api.cc

@@ -20828,6 +20828,37 @@ TEST(RunMicrotasksWithoutEnteringContext) {
 }
 
 
+static void DebugEventInObserver(const v8::Debug::EventDetails& event_details) {
+  v8::DebugEvent event = event_details.GetEvent();
+  if (event != v8::Break) return;
+  Handle<Object> exec_state = event_details.GetExecutionState();
+  Handle<Value> break_id = exec_state->Get(v8_str("break_id"));
+  CompileRun("function f(id) { new FrameDetails(id, 0); }");
+  Handle<Function> fun = Handle<Function>::Cast(
+      CcTest::global()->Get(v8_str("f"))->ToObject());
+  fun->Call(CcTest::global(), 1, &break_id);
+}
+
+
+TEST(Regress385349) {
+  i::FLAG_allow_natives_syntax = true;
+  v8::Isolate* isolate = CcTest::isolate();
+  HandleScope handle_scope(isolate);
+  isolate->SetAutorunMicrotasks(false);
+  Handle<Context> context = Context::New(isolate);
+  v8::Debug::SetDebugEventListener(DebugEventInObserver);
+  {
+    Context::Scope context_scope(context);
+    CompileRun("var obj = {};"
+               "Object.observe(obj, function(changes) { debugger; });"
+               "obj.a = 0;");
+  }
+  isolate->RunMicrotasks();
+  isolate->SetAutorunMicrotasks(true);
+  v8::Debug::SetDebugEventListener(NULL);
+}
+
+
 static int probes_counter = 0;
 static int misses_counter = 0;
 static int updates_counter = 0;