Make net::DataURL's MIME string check stricter

content/browser/renderer_host/pepper/pepper_file_system_browser_host.cc

 // Copyright 2013 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 "content/browser/renderer_host/pepper/pepper_file_system_browser_host.h"
 
 #include "base/bind.h"
 #include "base/callback.h"
 #include "content/browser/renderer_host/pepper/pepper_file_io_host.h"
 #include "content/browser/renderer_host/pepper/quota_reservation.h"
@@ skipping 467 matching lines @@
   // Use the first element in |info->mime_types| even if several elements exist.
   return info->mime_types[0].mime_type;
 }
 
 std::string PepperFileSystemBrowserHost::GeneratePluginId(
     const std::string& mime_type) const {
   // TODO(nhiroki): This function is very specialized for specific plugins (MIME
   // types).  If we bring this API to stable, we might have to make it more
   // general.
 
-  if (!net::IsMimeType(mime_type))
+  std::string top_level_type;
+  std::string subtype;
+  if (!net::ParseMimeTypeWithoutParameter(
+          mime_type, &top_level_type, &subtype) ||
+      !net::IsValidTopLevelMimeType(top_level_type))
     return std::string();
-  std::string output = mime_type;
 
   // Replace a slash used for type/subtype separator with an underscore.
-  // NOTE: This assumes there is only one slash in the MIME type.
-  ReplaceFirstSubstringAfterOffset(&output, 0, "/", "_");
+  std::string output = top_level_type + "_" + subtype;
 
   // Verify |output| contains only alphabets, digits, or "._-".
   for (std::string::const_iterator it = output.begin();
        it != output.end(); ++it) {
     if (!IsAsciiAlpha(*it) && !IsAsciiDigit(*it) &&
         *it != '.' && *it != '_' && *it != '-') {
       LOG(WARNING) << "Failed to generate a plugin id.";
       return std::string();
     }
   }
   return output;
 }
 
 }  // namespace content