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

Add a missing PPAPI_THUNK_EXPORT to PPB_Audio_Input_API.

BUG=none
TBR=viettrungluu@chromium.org

Review URL: http://codereview.chromium.org/8558012

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@110658 0039d316-1c4b-4281-b951-d872f2087c98

ppapi/thunk/ppb_audio_input_api.h

@@ -12,7 +12,7 @@
 namespace ppapi {
 namespace thunk {
 
-class PPB_AudioInput_API {
+class PPAPI_THUNK_EXPORT PPB_AudioInput_API {
  public:
   virtual ~PPB_AudioInput_API() {}