Require hosts for non-file URLs.

src/url_canon_stdurl.cc

 // Copyright 2007, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 // notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
@@ skipping 48 matching lines @@
       output->push_back('/');
     }
 
     // User info: the canonicalizer will handle the : and @.
     success &= CanonicalizeUserInfo(source.username, parsed.username,
                                     source.password, parsed.password,
                                     output,
                                     &new_parsed->username,
                                     &new_parsed->password);
 
-    // Host: always write if we have an authority (may be empty).
     success &= CanonicalizeHost(source.host, parsed.host,
                                 output, &new_parsed->host);
 
+    // Host must not be empty for standard URLs.
+    if (!parsed.host.is_nonempty())
+      success = false;
+
     // Port: the port canonicalizer will handle the colon.
     int default_port = DefaultPortForScheme(
         &output->data()[new_parsed->scheme.begin], new_parsed->scheme.len);
     success &= CanonicalizePort(source.port, parsed.port, default_port,
                                 output, &new_parsed->port);
   } else {
     // No authority, clear the components.
     have_authority = false;
     new_parsed->host.reset();
     new_parsed->username.reset();
@@ skipping 101 matching lines @@
                         url_parse::Parsed* new_parsed) {
   RawCanonOutput<1024> utf8;
   URLComponentSource<char> source(base);
   url_parse::Parsed parsed(base_parsed);
   SetupUTF16OverrideComponents(base, replacements, &utf8, &source, &parsed);
   return DoCanonicalizeStandardURL<char, unsigned char>(
       source, parsed, query_converter, output, new_parsed);
 }
 
 }  // namespace url_canon