Promoting the MHTML file extension to primary mappings.

net/base/mime_util.cc

 // Copyright (c) 2011 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 <map>
 #include <string>
 
 #include "net/base/mime_util.h"
 #include "net/base/platform_mime_util.h"
 
@@ skipping 77 matching lines @@
   { "image/png", "png" },
   { "video/mp4", "mp4,m4v" },
   { "audio/x-m4a", "m4a" },
   { "audio/mp3", "mp3" },
   { "video/ogg", "ogv,ogm" },
   { "audio/ogg", "ogg,oga" },
   { "video/webm", "webm" },
   { "audio/webm", "webm" },
   { "audio/wav", "wav" },
   { "application/xhtml+xml", "xhtml,xht" },
-  { "application/x-chrome-extension", "crx" }
+  { "application/x-chrome-extension", "crx" },
+  { "multipart/related", "mht,mhtml" }

[wtc, 2011/05/27 17:21:12]

Nit: it seems better to list mhtml before mht.
See line 97 above.

 };
 
 static const MimeInfo secondary_mappings[] = {
   { "application/octet-stream", "exe,com,bin" },
   { "application/gzip", "gz" },
   { "application/pdf", "pdf" },
   { "application/postscript", "ps,eps,ai" },
   { "application/x-javascript", "js" },
   { "image/bmp", "bmp" },
   { "image/x-icon", "ico" },
   { "image/jpeg", "jfif,pjpeg,pjp" },
   { "image/tiff", "tiff,tif" },
   { "image/x-xbitmap", "xbm" },
   { "image/svg+xml", "svg,svgz" },
   { "message/rfc822", "eml" },
   { "text/plain", "txt,text" },
   { "text/html", "shtml,ehtml" },
   { "application/rss+xml", "rss" },
   { "application/rdf+xml", "rdf" },
   { "text/xml", "xsl,xbl" },
   { "application/vnd.mozilla.xul+xml", "xul" },
-  { "application/x-shockwave-flash", "swf,swl" },
-  { "multipart/related", "mht,mhtml" }
+  { "application/x-shockwave-flash", "swf,swl" }
 };
 
 static const char* FindMimeType(const MimeInfo* mappings,
                                 size_t mappings_len,
                                 const char* ext) {
   size_t ext_len = strlen(ext);
 
   for (size_t i = 0; i < mappings_len; ++i) {
     const char* extensions = mappings[i].extensions;
     for (;;) {
@@ skipping 575 matching lines @@
 
   GetExtensionsFromHardCodedMappings(secondary_mappings,
                                      arraysize(secondary_mappings),
                                      mime_type,
                                      &unique_extensions);
 
   HashSetToVector(&unique_extensions, extensions);
 }
 
 }  // namespace net