When an Isolate is configured to use lockers, foreground tasks need to lock

gin/v8_platform.cc

Index: gin/v8_platform.cc
diff --git a/gin/v8_platform.cc b/gin/v8_platform.cc
index 945eee0cc3d9798730130ebbe44d3d5acb92d4f7..bbbf4d076a287c6b6a62c1cb0247e6d5ce6d5270 100644
--- a/gin/v8_platform.cc
+++ b/gin/v8_platform.cc
@@ -17,6 +17,11 @@ namespace {
 
 base::LazyInstance<V8Platform>::Leaky g_v8_platform = LAZY_INSTANCE_INITIALIZER;
 
+void RunWithLocker(v8::Isolate* isolate, v8::Task* task) {
+  v8::Locker lock(isolate);
+  task->Run();
+}
+
 }  // namespace
 
 // static
@@ -49,8 +54,15 @@ void V8Platform::CallOnBackgroundThread(
 }
 
 void V8Platform::CallOnForegroundThread(v8::Isolate* isolate, v8::Task* task) {
-  PerIsolateData::From(isolate)->task_runner()->PostTask(
-      FROM_HERE, base::Bind(&v8::Task::Run, base::Owned(task)));
+  PerIsolateData* data = PerIsolateData::From(isolate);

[ulan, 2016/11/04 14:28:30]

The same change should apply to other Call*OnForegroundThread functions?

+  if (data->access_mode() == IsolateHolder::kUseLocker) {
+    data->task_runner()->PostTask(
+        FROM_HERE, base::Bind(RunWithLocker, base::Unretained(isolate),
+                              base::Owned(task)));
+  } else {
+    data->task_runner()->PostTask(
+        FROM_HERE, base::Bind(&v8::Task::Run, base::Owned(task)));
+  }
 }
 
 void V8Platform::CallDelayedOnForegroundThread(v8::Isolate* isolate,