Move ReplaceStringPlaceholders to base namespace.

ios/web/webui/shared_resources_data_source_ios.cc

 // Copyright 2014 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 "ios/web/webui/shared_resources_data_source_ios.h"
 
 #include "base/logging.h"
 #include "base/memory/ref_counted_memory.h"
 #include "base/strings/string_util.h"
 #include "grit/webui_resources_map.h"
@@ skipping 45 matching lines @@
 
   if (idr == IDR_WEBUI_CSS_TEXT_DEFAULTS) {
     std::vector<std::string> placeholders;
     placeholders.push_back(webui::GetTextDirection());  // $1
     placeholders.push_back(webui::GetFontFamily());  // $2
     placeholders.push_back(webui::GetFontSize());  // $3
 
     const std::string& chrome_shared =
         web_client->GetDataResource(idr, ui::SCALE_FACTOR_NONE).as_string();
     std::string replaced =
-        ReplaceStringPlaceholders(chrome_shared, placeholders, nullptr);
+        base::ReplaceStringPlaceholders(chrome_shared, placeholders, nullptr);
     bytes = base::RefCountedString::TakeString(&replaced);
   } else {
     bytes = web_client->GetDataResourceBytes(idr);
   }
 
   callback.Run(bytes.get());
 }
 
 std::string SharedResourcesDataSourceIOS::GetMimeType(
     const std::string& path) const {
   std::string mime_type;
   net::GetMimeTypeFromFile(base::FilePath().AppendASCII(path), &mime_type);
   return mime_type;
 }
 
 }  // namespace web