Fix handling of URLs with no schema.

src/url_util.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 160 matching lines @@
   if (url_parse::DoesBeginUNCPath(spec, 0, spec_len, false) ||
       url_parse::DoesBeginWindowsDriveSpec(spec, 0, spec_len)) {
     url_parse::ParseFileURL(spec, spec_len, &parsed_input);
     return url_canon::CanonicalizeFileURL(spec, spec_len, parsed_input,
                                           charset_converter,
                                           output, output_parsed);
   }
 #endif
 
   url_parse::Component scheme;
-  if (!url_parse::ExtractScheme(spec, spec_len, &scheme))
+  if (!url_parse::ExtractScheme(spec, spec_len, &scheme)) {
+    AppendInvalidNarrowString(spec, 0, spec_len, output);
     return false;
+  }
 
   // This is the parsed version of the input URL, we have to canonicalize it
   // before storing it in our object.
   bool success;
   if (DoCompareSchemeComponent(spec, scheme, kFileScheme)) {
     // File URLs are special.
     url_parse::ParseFileURL(spec, spec_len, &parsed_input);
     success = url_canon::CanonicalizeFileURL(spec, spec_len, parsed_input,
                                              charset_converter, output,
                                              output_parsed);
@@ skipping 389 matching lines @@
   return DoCompareSchemeComponent(spec, component, compare_to);
 }
 
 bool CompareSchemeComponent(const char16* spec,
                             const url_parse::Component& component,
                             const char* compare_to) {
   return DoCompareSchemeComponent(spec, component, compare_to);
 }
 
 }  // namespace url_util