Make sure filters can handle an empty input buffer...

net/base/gzip_filter.cc

 // Copyright (c) 2006-2008 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.
 
 #include "net/base/gzip_filter.h"
 
 #include "base/logging.h"
 #include "net/base/gzip_header.h"
 #include "third_party/zlib/zlib.h"
 
@@ skipping 179 matching lines @@
   }
 
   return Filter::FILTER_ERROR;
 }
 
 Filter::FilterStatus GZipFilter::DoInflate(char* dest_buffer, int* dest_len) {
   // Make sure we have both valid input data and output buffer.
   if (!dest_buffer || !dest_len || *dest_len <= 0)  // output
     return Filter::FILTER_ERROR;
 
-  if (!next_stream_data_ || stream_data_len_ <= 0)  // input
-    return Filter::FILTER_ERROR;
+  if (!next_stream_data_ || stream_data_len_ <= 0) {  // input
+    *dest_len = 0;
+    return Filter::FILTER_NEED_MORE_DATA;
+  }
 
   // Fill in zlib control block
   zlib_stream_.get()->next_in = bit_cast<Bytef*>(next_stream_data_);
   zlib_stream_.get()->avail_in = stream_data_len_;
   zlib_stream_.get()->next_out = bit_cast<Bytef*>(dest_buffer);
   zlib_stream_.get()->avail_out = *dest_len;
 
   int inflate_code = MOZ_Z_inflate(zlib_stream_.get(), Z_NO_FLUSH);
   int bytesWritten = *dest_len - zlib_stream_.get()->avail_out;
 
@@ skipping 72 matching lines @@
   if (footer_bytes_expected > 0) {
     int footer_byte_avail = std::min(footer_bytes_expected, stream_data_len_);
     stream_data_len_ -= footer_byte_avail;
     next_stream_data_ += footer_byte_avail;
     gzip_footer_bytes_ += footer_byte_avail;
 
     if (stream_data_len_ == 0)
       next_stream_data_ = NULL;
   }
 }