Add an API to pump the message loop to libplatform

src/libplatform/default-platform.cc

Index: src/libplatform/default-platform.cc
diff --git a/src/libplatform/default-platform.cc b/src/libplatform/default-platform.cc
index 9a2c30dcdefa769913205aac21ab68352efaf8e9..a05ec7dedb102525ba6c21c3d6d79bada6a6d793 100644
--- a/src/libplatform/default-platform.cc
+++ b/src/libplatform/default-platform.cc
@@ -23,6 +23,11 @@ v8::Platform* CreateDefaultPlatform(int thread_pool_size) {
 }
 
 
+bool PumpMessageLoop(v8::Platform* platform, v8::Isolate* isolate) {
+  return reinterpret_cast<DefaultPlatform*>(platform)->PumpMessageLoop(isolate);
+}
+
+
 const int DefaultPlatform::kMaxThreadPoolSize = 4;
 
 
@@ -39,6 +44,14 @@ DefaultPlatform::~DefaultPlatform() {
       delete *i;
     }
   }
+  for (std::map<v8::Isolate*, std::queue<Task*> >::iterator i =
+           main_thread_queue_.begin();
+       i != main_thread_queue_.end(); ++i) {
+    while (!i->second.empty()) {
+      delete i->second.front();
+      i->second.pop();
+    }
+  }
 }
 
 
@@ -61,6 +74,24 @@ void DefaultPlatform::EnsureInitialized() {
     thread_pool_.push_back(new WorkerThread(&queue_));
 }
 
+
+bool DefaultPlatform::PumpMessageLoop(v8::Isolate* isolate) {
+  Task* task = NULL;
+  {
+    base::LockGuard<base::Mutex> guard(&lock_);
+    std::map<v8::Isolate*, std::queue<Task*> >::iterator it =
+        main_thread_queue_.find(isolate);
+    if (it == main_thread_queue_.end() || it->second.empty()) {
+      return false;
+    }
+    task = it->second.front();
+    it->second.pop();
+  }
+  task->Run();
+  delete task;
+  return true;
+}
+
 void DefaultPlatform::CallOnBackgroundThread(Task *task,
                                              ExpectedRuntime expected_runtime) {
   EnsureInitialized();
@@ -69,9 +100,8 @@ void DefaultPlatform::CallOnBackgroundThread(Task *task,
 
 
 void DefaultPlatform::CallOnForegroundThread(v8::Isolate* isolate, Task* task) {
-  // TODO(jochen): implement.
-  task->Run();
-  delete task;
+  base::LockGuard<base::Mutex> guard(&lock_);
+  main_thread_queue_[isolate].push(task);
 }
 
 } }  // namespace v8::platform