Componentization: make symbols visible.

public/platform/modules/navigator_services/WebServicePortProviderClient.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 WebServicePortProviderClient_h
 #define WebServicePortProviderClient_h
 
 #include "public/platform/WebCommon.h"
+#include "public/platform/WebMessagePortChannel.h"
+#include "public/platform/modules/navigator_services/WebServicePort.h"
 
 namespace blink {
 
+class WebString;
+
 // Interface implemented by blink, used for communication back from embedding
 // code to blink. An instance of this interface is passed to the embedder when
 // a WebServicePortProvider is created.
-class WebServicePortProviderClient {
+class BLINK_PLATFORM_EXPORT WebServicePortProviderClient {
 public:
     // Post a message to one of the ports owned by a ServicePortCollection.
     virtual void postMessage(WebServicePortID, const WebString&, const WebMessagePortChannelArray&) = 0;
 
 protected:
     virtual ~WebServicePortProviderClient() {}
 };
 
 } // namespace blink
 
 #endif // WebServicePortProviderClient_h