Fix a memory leak on the async resource handler.

net/base/io_buffer.h

 // Copyright (c) 2009 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 NET_BASE_IO_BUFFER_H_
 #define NET_BASE_IO_BUFFER_H_
 
+#include "base/logging.h"
 #include "base/ref_counted.h"
 
 namespace net {
 
 // This is a simple wrapper around a buffer that provides ref counting for
 // easier asynchronous IO handling.
 class IOBuffer : public base::RefCountedThreadSafe<IOBuffer> {
  public:
+  IOBuffer() : data_(NULL) {}
   explicit IOBuffer(int buffer_size) {
+    DCHECK(buffer_size);
     data_ = new char[buffer_size];
   }
   explicit IOBuffer(char* buffer) : data_(buffer) {}
   virtual ~IOBuffer() {
     delete[] data_;
   }
 
   char* data() { return data_; }
 
  protected:
   char* data_;
 };
 
 }  // namespace net
 
 #endif  // NET_BASE_IO_BUFFER_H_