When resolving URL, empty relative URL should remove ref component....

src/url_canon_relative.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 439 matching lines @@
   if (base_parsed.path.len <= 0) {
     // On error, return the input (resolving a relative URL on a non-relative
     // base = the base).
     int base_len = base_parsed.Length();
     for (int i = 0; i < base_len; i++)
       output->push_back(base_url[i]);
     return false;
   }
 
   if (relative_component.len <= 0) {
-    // Empty relative URL, make no changes.
+    // Empty relative URL, leave unchanged, only removing the ref component.
     int base_len = base_parsed.Length();
-    for (int i = 0; i < base_len; i++)
-      output->push_back(base_url[i]);
+    base_len -= base_parsed.ref.len + 1;
+    out_parsed->ref.reset();
+    output->Append(base_url, base_len);
     return true;
   }
 
   int num_slashes = url_parse::CountConsecutiveSlashes(
       relative_url, relative_component.begin, relative_component.end());
 
 #ifdef WIN32
   // On Windows, two slashes for a file path (regardless of which direction
   // they are) means that it's UNC. Two backslashes on any base scheme mean
   // that it's an absolute UNC path (we use the base_is_file flag to control
@@ skipping 88 matching lines @@
                         const url_parse::Component& relative_component,
                         CharsetConverter* query_converter,
                         CanonOutput* output,
                         url_parse::Parsed* out_parsed) {
   return DoResolveRelativeURL<char16>(
       base_url, base_parsed, base_is_file, relative_url,
       relative_component, query_converter, output, out_parsed);
 }
 
 }  // namespace url_canon