Fix up some types in the API.

ppapi/cpp/url_loader.h

 // Copyright (c) 2010 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_CPP_URL_LOADER_H_
 #define PPAPI_CPP_URL_LOADER_H_
 
 #include "ppapi/c/pp_stdint.h"
 #include "ppapi/cpp/resource.h"
 
@@ skipping 79 matching lines @@
 
   // PPB_URLLoader methods:
   int32_t Open(const URLRequestInfo& request_info,
                const CompletionCallback& cc);
   int32_t FollowRedirect(const CompletionCallback& cc);
   bool GetUploadProgress(int64_t* bytes_sent,
                          int64_t* total_bytes_to_be_sent) const;
   bool GetDownloadProgress(int64_t* bytes_received,
                            int64_t* total_bytes_to_be_received) const;
   URLResponseInfo GetResponseInfo() const;
-  int32_t ReadResponseBody(char* buffer,
+  int32_t ReadResponseBody(void* buffer,
                            int32_t bytes_to_read,
                            const CompletionCallback& cc);
   int32_t FinishStreamingToFile(const CompletionCallback& cc);
   void Close();
 };
 
 }  // namespace pp
 
 #endif  // PPAPI_CPP_URL_LOADER_H_