[ABANDONED] Introduce Promise example implementation written in JavaScript.

Source/core/dom/Promise.js

 /*
  * 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 10 matching lines @@
  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#ifndef Task_h
-#define Task_h
-
-#include "wtf/Functional.h"
-#include "public/platform/WebThread.h"
-
-namespace WebCore {
-
-class Task : public WebKit::WebThread::Task {
-public:
-    explicit Task(const Closure& closure)
-        : m_closure(closure)
+(function() {
+    function get(value)
     {
+        var old = this.value;
+        this.value = value;
+        return old;
     }
 
-    virtual void run() OVERRIDE
+    function getStatic(value)
     {
-        m_closure();
+        return new Promise(value);
     }
 
-private:
-    Closure m_closure;
-};
+    function concat(a, b)
+    {
+        // We must not use the method of |a|, since its prototype object can be modified.
+        return [].concat(a, b);
+    }
 
-} // namespace WebCore
+    function $Promise(value)
+    {
+        this.value = value;
+    }
 
-#endif // Task_h
+    $Promise.prototype = {
+        get: get
+    };
+    $Promise.getStatic = getStatic;
+    $Promise.concat = concat;
+    return $Promise;
+});