requestIdleCallback: Yield for high priority work

third_party/WebKit/Source/core/dom/IdleDeadline.h

 // Copyright 2015 The Chromium 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 IdleDeadline_h
 #define IdleDeadline_h
 
 #include "bindings/core/v8/ScriptWrappable.h"
 #include "platform/heap/Handle.h"
 
 namespace blink {
 
-class IdleDeadline : public GarbageCollected<IdleDeadline>,
-                     public ScriptWrappable {
+class CORE_EXPORT IdleDeadline : public GarbageCollected<IdleDeadline>,
+                                 public ScriptWrappable {
   DEFINE_WRAPPERTYPEINFO();
 
  public:
   enum class CallbackType { CalledWhenIdle, CalledByTimeout };
 
   static IdleDeadline* create(double deadlineSeconds,
                               CallbackType callbackType) {
     return new IdleDeadline(deadlineSeconds, callbackType);
   }
 
   DEFINE_INLINE_TRACE() {}
 
   double timeRemaining() const;
 
   bool didTimeout() const {
     return m_callbackType == CallbackType::CalledByTimeout;
   }
 
  private:
   IdleDeadline(double deadlineSeconds, CallbackType);
 
   double m_deadlineSeconds;
   CallbackType m_callbackType;
 };
 
 }  // namespace blink
 
 #endif  // IdleDeadline_h