Make all PDF-related file extensions non-"dangerous".

chrome/browser/download/download_extensions.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 <set>
 #include <string>
 
 #include "chrome/browser/download/download_extensions.h"
 
 #include "base/strings/string_util.h"
@@ skipping 50 matching lines @@
     DownloadDangerLevel level;
 } g_executables[] = {
 // Chrome OS does not suffer from some of the problems of older OS'es.
 #if !defined(OS_CHROMEOS)
   // Relating to Java.
   { "class", DANGEROUS },
   { "jar", DANGEROUS },
   { "jnlp", DANGEROUS },
 #endif
 #if !defined(OS_CHROMEOS) && !defined(OS_ANDROID)
-  // Relating to PDF. ".pdf" per se is not considered dangerous.
-  { "pdfxml", ALLOW_ON_USER_GESTURE },
-  { "mars", ALLOW_ON_USER_GESTURE },
-  { "fdf", ALLOW_ON_USER_GESTURE },
-  { "xfdf", ALLOW_ON_USER_GESTURE },
-  { "xdp", ALLOW_ON_USER_GESTURE },
-  { "xfd", ALLOW_ON_USER_GESTURE },
   // Relating to scripting languages.
   { "pl", ALLOW_ON_USER_GESTURE },
   { "py", ALLOW_ON_USER_GESTURE },
   { "pyc", ALLOW_ON_USER_GESTURE },
   { "pyw", ALLOW_ON_USER_GESTURE },
   { "rb", ALLOW_ON_USER_GESTURE },
 #endif
   // Some files are dangerous on all platforms.
   // Flash files downloaded locally can sometimes access the local filesystem.
   { "swf", ALLOW_ON_USER_GESTURE },
@@ skipping 185 matching lines @@
   for (size_t i = 0; i < arraysize(kExecutableBlackList); ++i) {
     if (net::MatchesMimeType(kExecutableBlackList[i], mime_type))
       return false;
   }
   // We consider only other application types to be executable.
   return net::MatchesMimeType("application/*", mime_type);
 }
 
 
 }  // namespace download_util