[WIP] make GURL::path() return a StringPiece

extensions/common/url_pattern.cc

 // Copyright (c) 2012 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 "extensions/common/url_pattern.h"
 
 #include <stddef.h>
 
 #include <ostream>
 
@@ skipping 352 matching lines @@
   }
 
   if (!MatchesScheme(test_url->scheme()))
     return false;
 
   if (match_all_urls_)
     return true;
 
   std::string path_for_request = test.PathForRequest();
   if (has_inner_url)
-    path_for_request = test_url->path() + path_for_request;
+    path_for_request = test_url->path().as_string() + path_for_request;
 
   return MatchesSecurityOriginHelper(*test_url) &&
          MatchesPath(path_for_request);
 }
 
 bool URLPattern::MatchesSecurityOrigin(const GURL& test) const {
   const GURL* test_url = &test;
   bool has_inner_url = test.inner_url() != NULL;
 
   if (has_inner_url) {
@@ skipping 231 matching lines @@
   }
 
   return result;
 }
 
 // static
 const char* URLPattern::GetParseResultString(
     URLPattern::ParseResult parse_result) {
   return kParseResultMessages[parse_result];
 }