Use text/plain as a test MIME type instead of application/pdf.

net/base/net_util_unittest.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 "net/base/net_util.h"
 
 #include <string.h>
 
 #include <algorithm>
 
@@ skipping 2271 matching lines @@
       "",
       "application/x-sh",
       L"download",
       L"bar.sh"
     },
     { // http://crbug.com/61571
       "http://www.example.com/npdf.php?fn=foobar.pdf",
       "",
       "",
       "",
-      "application/pdf",
+      "text/plain",
       L"download",
-      L"npdf.pdf"
+      L"npdf" TXT_EXT
     },
     { // Shouldn't overwrite C-D specified extension.
       "http://www.example.com/npdf.php?fn=foobar.pdf",
       "Content-Disposition: filename=foobar.jpg",
       "",
       "",
-      "application/pdf",
+      "text/plain",
       L"download",
       L"foobar.jpg"
     },
     { // http://crbug.com/87719
       "http://www.example.com/image.aspx?id=blargh",
       "",
       "",
       "",
       "image/jpeg",
       L"download",
@@ skipping 1122 matching lines @@
       if (it->address[i] != 0) {
         all_zeroes = false;
         break;
       }
     }
     EXPECT_FALSE(all_zeroes);
   }
 }
 
 }  // namespace net