Attempt to fix win_shared bot following http://crrev.com/110587

ppapi/thunk/ppb_audio_input_api.h

 // Copyright (c) 2011 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 PPAPI_THUNK_AUDIO_INPUT_API_H_
 #define PPAPI_THUNK_AUDIO_INPUT_API_H_
 
 #include "ppapi/c/dev/ppb_audio_input_dev.h"
 #include "ppapi/c/pp_completion_callback.h"
 #include "ppapi/thunk/ppapi_thunk_export.h"
 
 namespace ppapi {
 namespace thunk {
 
-class PPB_AudioInput_API {
+class PPAPI_THUNK_EXPORT PPB_AudioInput_API {
  public:
   virtual ~PPB_AudioInput_API() {}
 
   virtual PP_Resource GetCurrentConfig() = 0;
   virtual PP_Bool StartCapture() = 0;
   virtual PP_Bool StopCapture() = 0;
 
   // Trusted API.
   virtual int32_t OpenTrusted(PP_Resource config_id,
                               PP_CompletionCallback create_callback) = 0;
   virtual int32_t GetSyncSocket(int* sync_socket) = 0;
   virtual int32_t GetSharedMemory(int* shm_handle, uint32_t* shm_size) = 0;
 };
 
 }  // namespace thunk
 }  // namespace ppapi
 
 #endif  // PPAPI_THUNK_AUDIO_INPUT_API_H_