Add thread affinity and ASSERT() for same-thread restriction to WTF::Function

third_party/WebKit/Source/platform/Task.h

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 22 matching lines @@
 
 #include "public/platform/WebTaskRunner.h"
 #include "wtf/Allocator.h"
 #include "wtf/Functional.h"
 #include "wtf/Noncopyable.h"
 #include "wtf/OwnPtr.h"
 #include "wtf/PassOwnPtr.h"
 
 namespace blink {
 
-class Task : public WebTaskRunner::Task {
-    USING_FAST_MALLOC(Task);
-    WTF_MAKE_NONCOPYABLE(Task);
+// Please use WTF::SameThreadClosure or WTF::CrossThreadClosure directly,
+// instead of wrapping them by blink::SameThreadTask/CrossThreadTask here.
+
+// TODO(hiroshige): Make these classes internal to
+// Source/platform/WebTaskRunner.cpp.
+class SameThreadTask : public WebTaskRunner::Task {
+    USING_FAST_MALLOC(SameThreadTask);
+    WTF_MAKE_NONCOPYABLE(SameThreadTask);
 public:
-    explicit Task(PassOwnPtr<Closure> closure)
+    explicit SameThreadTask(PassOwnPtr<SameThreadClosure> closure)
         : m_closure(std::move(closure))
     {
     }
+
+    void run() override
+    {
+        (*m_closure)();
+    }
+
+private:
+    OwnPtr<SameThreadClosure> m_closure;
+};
+
+class CrossThreadTask : public WebTaskRunner::Task {
+    USING_FAST_MALLOC(CrossThreadTask);
+    WTF_MAKE_NONCOPYABLE(CrossThreadTask);
+public:
+    explicit CrossThreadTask(PassOwnPtr<CrossThreadClosure> closure)
+        : m_closure(std::move(closure))
+    {
+    }
 
     void run() override
     {
         (*m_closure)();
     }
 
 private:
-    OwnPtr<Closure> m_closure;
+    OwnPtr<CrossThreadClosure> m_closure;
 };
 
 } // namespace blink
 
 #endif // Task_h