Add V8 platform API to call delayed task.

include/v8-platform.h

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_V8_PLATFORM_H_
 #define V8_V8_PLATFORM_H_
 
 namespace v8 {
 
 class Isolate;
@@ skipping 39 matching lines @@
                                       ExpectedRuntime expected_runtime) = 0;
 
   /**
    * Schedules a task to be invoked on a foreground thread wrt a specific
    * |isolate|. Tasks posted for the same isolate should be execute in order of
    * scheduling. The definition of "foreground" is opaque to V8.
    */
   virtual void CallOnForegroundThread(Isolate* isolate, Task* task) = 0;
 
   /**
+   * Schedules a task to be invoked on a foreground thread wrt a specific
+   * |isolate| after the given number of seconds |delay_in_seconds|.
+   * Tasks posted for the same isolate should be execute in order of
+   * scheduling. The definition of "foreground" is opaque to V8.
+   */
+  virtual void CallDelayedOnForegroundThread(Isolate* isolate, Task* task,
+                                             double delay_in_seconds) {
+    // TODO(ulan): Make this function abstract after V8 roll in Chromium.
+  }
+
+  /**
    * Monotonically increasing time in seconds from an arbitrary fixed point in
    * the past. This function is expected to return at least
    * millisecond-precision values. For this reason,
    * it is recommended that the fixed point be no further in the past than
    * the epoch.
    **/
   virtual double MonotonicallyIncreasingTime() = 0;
 };
 
 }  // namespace v8
 
 #endif  // V8_V8_PLATFORM_H_