Simplify createCrossThreadTask()

third_party/WebKit/Source/core/dom/ExecutionContextTask.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.
  *     * Neither the name of Google Inc. nor the names of its
@@ skipping 32 matching lines @@
     USING_FAST_MALLOC(ExecutionContextTask);
 public:
     ExecutionContextTask() { }
     virtual ~ExecutionContextTask() { }
     virtual void performTask(ExecutionContext*) = 0;
     virtual String taskNameForInstrumentation() const { return String(); }
 };
 
 namespace internal {
 
+template<WTF::FunctionThreadAffinity threadAffinity>
+void runCallClosureTask(std::unique_ptr<Function<void(), threadAffinity>> closure, ExecutionContext*)
+{
+    (*closure)();
+}
+
+template<WTF::FunctionThreadAffinity threadAffinity>
+void runCallClosureTask(std::unique_ptr<Function<void(ExecutionContext*), threadAffinity>> closure, ExecutionContext* executionContext)
+{
+    (*closure)(executionContext);
+}
+
 template<typename T, WTF::FunctionThreadAffinity threadAffinity>
-class CallClosureTaskBase : public ExecutionContextTask {
-protected:
-    explicit CallClosureTaskBase(std::unique_ptr<Function<T, threadAffinity>> closure)
+class CallClosureTask final : public ExecutionContextTask {
+public:
+    static std::unique_ptr<CallClosureTask> create(std::unique_ptr<Function<T, threadAffinity>> closure)
+    {
+        return wrapUnique(new CallClosureTask(std::move(closure)));
+    }
+
+private:
+    explicit CallClosureTask(std::unique_ptr<Function<T, threadAffinity>> closure)
         : m_closure(std::move(closure))
     {
     }
 
+    void performTask(ExecutionContext* executionContext) override
+    {
+        runCallClosureTask(std::move(m_closure), executionContext);
+    }
+
     std::unique_ptr<Function<T, threadAffinity>> m_closure;
 };
 
-template<WTF::FunctionThreadAffinity threadAffinity>
-class CallClosureTask final : public CallClosureTaskBase<void(), threadAffinity> {
-public:
-    // Do not use |create| other than in createCrossThreadTask and
-    // createSameThreadTask.
-    // See http://crbug.com/390851
-    static std::unique_ptr<CallClosureTask<threadAffinity>> create(std::unique_ptr<Function<void(), threadAffinity>> closure)
-    {
-        return wrapUnique(new CallClosureTask<threadAffinity>(std::move(closure)));
-    }
-
-    void performTask(ExecutionContext*) override
-    {
-        (*this->m_closure)();
-    }
-
-private:
-    explicit CallClosureTask(std::unique_ptr<Function<void(), threadAffinity>> closure)
-        : CallClosureTaskBase<void(), threadAffinity>(std::move(closure))
-    {
-    }
-};
-
-template<WTF::FunctionThreadAffinity threadAffinity>
-class CallClosureWithExecutionContextTask final : public CallClosureTaskBase<void(ExecutionContext*), threadAffinity> {
-public:
-    // Do not use |create| other than in createCrossThreadTask and
-    // createSameThreadTask.
-    // See http://crbug.com/390851
-    static std::unique_ptr<CallClosureWithExecutionContextTask> create(std::unique_ptr<Function<void(ExecutionContext*), threadAffinity>> closure)
-    {
-        return wrapUnique(new CallClosureWithExecutionContextTask(std::move(closure)));
-    }
-
-    void performTask(ExecutionContext* context) override
-    {
-        (*this->m_closure)(context);
-    }
-
-private:
-    explicit CallClosureWithExecutionContextTask(std::unique_ptr<Function<void(ExecutionContext*), threadAffinity>> closure)
-        : CallClosureTaskBase<void(ExecutionContext*), threadAffinity>(std::move(closure))
-    {
-    }
-};
+// Do not use |create| other than in createCrossThreadTask and
+// createSameThreadTask.
+// See http://crbug.com/390851
+template<typename T, WTF::FunctionThreadAffinity threadAffinity>
+std::unique_ptr<CallClosureTask<T, threadAffinity>> createCallClosureTask(std::unique_ptr<Function<T, threadAffinity>> closure)
+{
+    return CallClosureTask<T, threadAffinity>::create(std::move(closure));
+}
 
 } // namespace internal
 
 // Create tasks passed within a single thread.
 // When posting tasks within a thread, use |createSameThreadTask| instead
 // of using |bind| directly to state explicitly that there is no need to care
 // about thread safety when posting the task.
 // When posting tasks across threads, use |createCrossThreadTask|.
 template<typename FunctionType, typename... P>
 std::unique_ptr<ExecutionContextTask> createSameThreadTask(
     FunctionType function, P&&... parameters)
 {
-    return internal::CallClosureTask<WTF::SameThreadAffinity>::create(bind(function, std::forward<P>(parameters)...));
+    return internal::createCallClosureTask(bind(function, std::forward<P>(parameters)...));
 }
 
 } // namespace blink
 
 #endif