Delete unused code in mimeutil.

net/base/mime_util.h

 // 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.
 
 #ifndef NET_BASE_MIME_UTIL_H__
 #define NET_BASE_MIME_UTIL_H__
 
 #include <string>
 #include <vector>
 
@@ skipping 28 matching lines @@
     FilePath::StringType* extension);
 
 // Check to see if a particular MIME type is in our list.
 NET_EXPORT bool IsSupportedImageMimeType(const std::string& mime_type);
 NET_EXPORT bool IsSupportedMediaMimeType(const std::string& mime_type);
 NET_EXPORT bool IsSupportedNonImageMimeType(const std::string& mime_type);
 NET_EXPORT bool IsUnsupportedTextMimeType(const std::string& mime_type);
 NET_EXPORT bool IsSupportedJavascriptMimeType(const std::string& mime_type);
 NET_EXPORT bool IsSupportedCertificateMimeType(const std::string& mime_type);
 
-// Get whether this mime type should be displayed in view-source mode.
-// (For example, XML.)
-NET_EXPORT bool IsViewSourceMimeType(const std::string& mime_type);
-
 // Convenience function.
 NET_EXPORT bool IsSupportedMimeType(const std::string& mime_type);
 
 // Returns true if this the mime_type_pattern matches a given mime-type.
 // Checks for absolute matching and wildcards.  mime-types should be in
 // lower case.
 NET_EXPORT bool MatchesMimeType(const std::string& mime_type_pattern,
                                 const std::string& mime_type);
 
 // Returns true if the |type_string| is a correctly-formed mime type specifier.
@@ skipping 56 matching lines @@
 #include "net/base/mime_util_certificate_type_list.h"
 #undef CERTIFICATE_MIME_TYPE
 };
 
 NET_EXPORT CertificateMimeType GetCertificateMimeTypeForMimeType(
     const std::string& mime_type);
 
 }  // namespace net
 
 #endif  // NET_BASE_MIME_UTIL_H__