[net] Remove logic for fixing up Gzip encoding type for downloads.

net/filter/filter.h

 // Copyright 2014 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.
 //
 // Filter performs filtering on data streams. Sample usage:
 //
 //   IStream* pre_filter_source;
 //   ...
 //   Filter* filter = Filter::Factory(filter_type, size);
 //   int pre_filter_data_len = filter->stream_buffer_size();
@@ skipping 84 matching lines @@
 
   // What mime type was specified in the header for this data?
   // Only makes senses for some types of contexts, and returns false
   // when not applicable.
   virtual bool GetMimeType(std::string* mime_type) const = 0;
 
   // What URL was used to access this data?
   // Return false if gurl is not present.
   virtual bool GetURL(GURL* gurl) const = 0;
 
-  // What Content-Disposition header came with this data?
-  // Return false if no header was present.
-  virtual bool GetContentDisposition(std::string* disposition) const = 0;
-
   // When was this data requested from a server?
   virtual base::Time GetRequestTime() const = 0;
 
   // Is data supplied from cache, or fresh across the net?
   virtual bool IsCachedContent() const = 0;
 
-  // Is this a download?
-  virtual bool IsDownload() const = 0;
-
   // Was this data flagged as a response to a request with an SDCH dictionary?
   virtual SdchManager::DictionarySet* SdchDictionariesAdvertised() const = 0;
 
   // How many bytes were read from the net or cache so far (and potentially
   // pushed into a filter for processing)?
   virtual int64 GetByteReadCount() const = 0;
 
   // What response code was received with the associated network transaction?
   // For example: 200 is ok.  4xx are error codes. etc.
   virtual int GetResponseCode() const = 0;
@@ skipping 185 matching lines @@
 
   // The filter type this filter was constructed from.
   FilterType type_id_;
 
   DISALLOW_COPY_AND_ASSIGN(Filter);
 };
 
 }  // namespace net
 
 #endif  // NET_FILTER_FILTER_H__