Support for png images served with "image/x-png" mime type

net/base/mime_util.cc

 // Copyright (c) 2012 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 <algorithm>
 #include <iterator>
 #include <map>
 #include <string>
 
 #include "base/containers/hash_tables.h"
@@ skipping 140 matching lines @@
   { "application/postscript", "ps,eps,ai" },
   { "application/javascript", "js" },
   { "application/font-woff", "woff" },
   { "image/bmp", "bmp" },
   { "image/x-icon", "ico" },
   { "image/vnd.microsoft.icon", "ico" },
   { "image/jpeg", "jfif,pjpeg,pjp" },
   { "image/tiff", "tiff,tif" },
   { "image/x-xbitmap", "xbm" },
   { "image/svg+xml", "svg,svgz" },
+  { "image/x-png", "png"},
   { "message/rfc822", "eml" },
   { "text/plain", "txt,text" },
   { "text/html", "ehtml" },
   { "application/rss+xml", "rss" },
   { "application/rdf+xml", "rdf" },
   { "text/xml", "xsl,xbl,xslt" },
   { "application/vnd.mozilla.xul+xml", "xul" },
   { "application/x-shockwave-flash", "swf,swl" },
   { "application/pkcs7-mime", "p7m,p7c,p7z" },
   { "application/pkcs7-signature", "p7s" }
@@ skipping 82 matching lines @@
 static const char* const supported_image_types[] = {
   "image/jpeg",
   "image/pjpeg",
   "image/jpg",
   "image/webp",
   "image/png",
   "image/gif",
   "image/bmp",
   "image/vnd.microsoft.icon",    // ico
   "image/x-icon",    // ico
-  "image/x-xbitmap"  // xbm
+  "image/x-xbitmap",  // xbm
+  "image/x-png"
 };
 
 // A list of media types: http://en.wikipedia.org/wiki/Internet_media_type
 // A comprehensive mime type list: http://plugindoc.mozdev.org/winmime.php
 // This set of codecs is supported by all variations of Chromium.
 static const char* const common_media_types[] = {
   // Ogg.
   "audio/ogg",
   "application/ogg",
 #if !defined(OS_ANDROID)  // Android doesn't support Ogg Theora.
@@ skipping 760 matching lines @@
   post_data->append("\r\n" + value + "\r\n");
 }
 
 void AddMultipartFinalDelimiterForUpload(const std::string& mime_boundary,
                                          std::string* post_data) {
   DCHECK(post_data);
   post_data->append("--" + mime_boundary + "--\r\n");
 }
 
 }  // namespace net