IWYU fixes for url/...

url/url_canon_relative.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.
 
 // Canonicalizer functions for working with and resolving relative URLs.
 
+#include <ostream>
+
 #include "base/logging.h"
+#include "base/strings/string16.h"
+#include "url/third_party/mozilla/url_parse.h"
 #include "url/url_canon.h"
 #include "url/url_canon_internal.h"
 #include "url/url_constants.h"
-#include "url/url_file.h"
+#include "url/url_file.h"  // IWYU pragma: keep
 #include "url/url_parse_internal.h"
 #include "url/url_util_internal.h"
 
 namespace url {
 
 namespace {
 
 // Firefox does a case-sensitive compare (which is probably wrong--Mozilla bug
 // 379034), whereas IE is case-insensitive.
 //
@@ skipping 533 matching lines @@
                         const Component& relative_component,
                         CharsetConverter* query_converter,
                         CanonOutput* output,
                         Parsed* out_parsed) {
   return DoResolveRelativeURL<base::char16>(
       base_url, base_parsed, base_is_file, relative_url,
       relative_component, query_converter, output, out_parsed);
 }
 
 }  // namespace url