Fix an unitialized variable warning in Brotli.

third_party/brotli/enc/encode.cc

 /* Copyright 2013 Google Inc. All Rights Reserved.
 
    Distributed under MIT license.
    See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
 */
 
 // Implementation of Brotli compressor.
 
 #include "./encode.h"
 
@@ skipping 1137 matching lines @@
     }
     delete[] storage;
     delete[] table;
     delete[] command_buf;
     delete[] literal_buf;
     return ok;
   }
 
   size_t in_bytes = 0;
   size_t out_bytes = 0;
-  uint8_t* output;
+  uint8_t* output = NULL;
   bool final_block = false;
   BrotliCompressor compressor(params);
   if (dictsize != 0) compressor.BrotliSetCustomDictionary(dictsize, dict);
   while (!final_block) {
     if (!CopyOneBlockToRingBuffer(in, &compressor, &in_bytes, &final_block)) {
       return false;
     }
     out_bytes = 0;
     if (!compressor.WriteBrotliData(final_block,
                                     /* force_flush = */ false,
                                     &out_bytes, &output)) {
       return false;
     }
     if (out_bytes > 0 && !out->Write(output, out_bytes)) {
       return false;
     }
   }
   return true;
 }
 
 
 }  // namespace brotli