Merge definitions of PlatformFileToInt and IntToPlatformFile to one place.

ppapi/proxy/ppb_audio_proxy.cc

Index: ppapi/proxy/ppb_audio_proxy.cc
diff --git a/ppapi/proxy/ppb_audio_proxy.cc b/ppapi/proxy/ppb_audio_proxy.cc
index 2e5775b191ec3b69c0c3d1299644b34c530ee643..614d482d495200f5615b5ef77042b62bc0ec69cc 100644
--- a/ppapi/proxy/ppb_audio_proxy.cc
+++ b/ppapi/proxy/ppb_audio_proxy.cc
@@ -115,22 +115,6 @@ int32_t Audio::GetSharedMemory(int* shm_handle, uint32_t* shm_size) {
   return PP_ERROR_NOTSUPPORTED;  // Don't proxy the trusted interface.
 }
 
-namespace {
-
-base::PlatformFile IntToPlatformFile(int32_t handle) {
-  // TODO(piman/brettw): Change trusted interface to return a PP_FileHandle,
-  // those casts are ugly.
-#if defined(OS_WIN)
-  return reinterpret_cast<HANDLE>(static_cast<intptr_t>(handle));
-#elif defined(OS_POSIX)
-  return handle;
-#else
-  #error Not implemented.
-#endif
-}
-
-}  // namespace
-
 PPB_Audio_Proxy::PPB_Audio_Proxy(Dispatcher* dispatcher)
     : InterfaceProxy(dispatcher),
       callback_factory_(ALLOW_THIS_IN_INITIALIZER_LIST(this)) {