Oilpan: fix build after r197794.

Source/modules/navigatorconnect/ServicePortCollection.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 ServicePortCollection_h
 #define ServicePortCollection_h
 
 #include "bindings/core/v8/ScriptPromise.h"
 #include "core/dom/ContextLifecycleObserver.h"
 #include "core/events/EventTarget.h"
 #include "modules/ModulesExport.h"
+#include "platform/heap/Handle.h"
 #include "public/platform/modules/navigator_services/WebServicePortProvider.h"
 #include "public/platform/modules/navigator_services/WebServicePortProviderClient.h"
 #include "wtf/RefCounted.h"
 
 namespace blink {
 
 class ServicePort;
 class ServicePortConnectOptions;
 class ServicePortMatchOptions;
 
 class MODULES_EXPORT ServicePortCollection final
     : public RefCountedGarbageCollectedEventTargetWithInlineData<ServicePortCollection>
     , public ContextLifecycleObserver
     , public WebServicePortProviderClient {
     DEFINE_WRAPPERTYPEINFO();
     REFCOUNTED_GARBAGE_COLLECTED_EVENT_TARGET(ServicePortCollection);
     WTF_MAKE_NONCOPYABLE(ServicePortCollection);
+    WILL_BE_USING_GARBAGE_COLLECTED_MIXIN(ServicePortCollection);
 public:
     static ServicePortCollection* create(ExecutionContext*);
     ~ServicePortCollection() override;
 
     // Adds a port to this collection to keep track of it and allow delivering
     // events related to it.
     void addPort(ServicePort*);
 
     // Called when a port is closed to signal the WebServicePortProvider as well
     // as remove the port from this collection.
@@ skipping 21 matching lines @@
 private:
     explicit ServicePortCollection(ExecutionContext*);
 
     OwnPtr<WebServicePortProvider> m_provider;
     HeapVector<Member<ServicePort>> m_ports;
 };
 
 } // namespace blink
 
 #endif // ServicePortCollection_h