Change uses of base::JoinString to pass StringPieces where possible.

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>
 
 #include "base/macros.h"
 #include "base/strings/pattern.h"
 #include "base/strings/string_number_conversions.h"
-#include "base/strings/string_piece.h"
 #include "base/strings/string_split.h"
 #include "base/strings/string_util.h"
 #include "base/strings/stringprintf.h"
 #include "content/public/common/url_constants.h"
 #include "extensions/common/constants.h"
 #include "net/base/registry_controlled_domains/registry_controlled_domain.h"
 #include "url/gurl.h"
 #include "url/url_util.h"
 
 const char URLPattern::kAllUrlsPattern[] = "<all_urls>";
@@ skipping 215 matching lines @@
 
     if (host_end_pos == base::StringPiece::npos)
       return PARSE_ERROR_EMPTY_PATH;
 
     // TODO(devlin): This whole series is expensive. Luckily we don't do it
     // *too* often, but it could be optimized.
     pattern.substr(host_start_pos, host_end_pos - host_start_pos)
         .CopyToString(&host_);
 
     // The first component can optionally be '*' to match all subdomains.
-    std::vector<std::string> host_components = base::SplitString(
+    std::vector<base::StringPiece> host_components = base::SplitStringPiece(
         host_, ".", base::TRIM_WHITESPACE, base::SPLIT_WANT_ALL);
 
     // Could be empty if the host only consists of whitespace characters.
     if (host_components.empty() ||
         (host_components.size() == 1 && host_components[0].empty()))
       return PARSE_ERROR_EMPTY_HOST;
 
     if (host_components[0] == "*") {
       match_subdomains_ = true;
       host_components.erase(host_components.begin(),
@@ skipping 362 matching lines @@
   }
 
   return result;
 }
 
 // static
 const char* URLPattern::GetParseResultString(
     URLPattern::ParseResult parse_result) {
   return kParseResultMessages[parse_result];
 }