POSIX: treat multiple extensions like .tar.gz as a single extension.

net/base/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/filter.h"
 
 #include "base/file_path.h"
 #include "base/string_util.h"
 #include "net/base/gzip_filter.h"
 #include "net/base/io_buffer.h"
@@ skipping 90 matching lines @@
     FilePath::StringType extension = filename.Extension();
 
     if (filter_context.IsDownload()) {
       // We don't want to decompress gzipped files when the user explicitly
       // asks to download them.
       // For the case of svgz files, we use the extension to distinguish
       // between svgz files and svg files compressed with gzip by the server.
       // When viewing a .svgz file, we need to uncompress it, but we don't
       // want to do that when downloading.
       // See Firefox's nonDecodableExtensions in nsExternalHelperAppService.cpp
-      if (FILE_PATH_LITERAL(".gz" == extension) ||
-          FILE_PATH_LITERAL(".tgz" == extension) ||
-          FILE_PATH_LITERAL(".svgz") == extension)
+      if (EndsWith(extension, FILE_PATH_LITERAL(".gz"), false) ||
+          LowerCaseEqualsASCII(extension, ".tgz") ||
+          LowerCaseEqualsASCII(extension, ".svgz"))
         encoding_types->clear();
     } else {
       // When the user does not explicitly ask to download a file, if we get a
       // supported mime type, then we attempt to decompress in order to view it.
       // However, if it's not a supported mime type, then we will attempt to
       // download it, and in that case, don't decompress .gz/.tgz files.
-      if ((FILE_PATH_LITERAL(".gz" == extension) ||
-           FILE_PATH_LITERAL(".tgz") == extension) &&
+      if ((EndsWith(extension, FILE_PATH_LITERAL(".gz"), false) ||
+           LowerCaseEqualsASCII(extension, ".tgz")) &&
           !net::IsSupportedMimeType(mime_type))
         encoding_types->clear();
     }
   }
 
   // If the request was for SDCH content, then we might need additional fixups.
   if (!filter_context.IsSdchResponse()) {
     // It was not an SDCH request, so we'll just record stats.
     if (1 < encoding_types->size()) {
       // Multiple filters were intended to only be used for SDCH (thus far!)
@@ skipping 252 matching lines @@
 
   DCHECK(stream_buffer());
   // Bail out if there is more data in the stream buffer to be filtered.
   if (!stream_buffer() || stream_data_len_)
     return false;
 
   next_stream_data_ = stream_buffer()->data();
   stream_data_len_ = stream_data_len;
   return true;
 }