Port more String and HashMap usages

sky/shell/dart/dart_library_provider_files.cc

 // Copyright 2015 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 "sky/shell/dart/dart_library_provider_files.h"
 
 #include "base/bind.h"
 #include "base/files/file_util.h"
 #include "base/strings/string_util.h"
 #include "base/threading/worker_pool.h"
@@ skipping 32 matching lines @@
     const base::FilePath& package_root)
     : package_root_(package_root) {
     CHECK(base::DirectoryExists(package_root_)) << "Invalid --package-root "
       << "\"" << package_root_.LossyDisplayName() << "\"";
 }
 
 DartLibraryProviderFiles::~DartLibraryProviderFiles() {
 }
 
 void DartLibraryProviderFiles::GetLibraryAsStream(
-    const String& name,
+    const std::string& name,
     blink::DataPipeConsumerCallback callback) {
   mojo::DataPipe pipe;
   callback.Run(pipe.consumer_handle.Pass());
 
-  base::FilePath source(name.toUTF8());
+  base::FilePath source(name);
   scoped_refptr<base::TaskRunner> runner =
       base::WorkerPool::GetTaskRunner(true);
   mojo::common::CopyFromFile(source, pipe.producer_handle.Pass(), 0,
                              runner.get(), base::Bind(&CopyComplete, source));
 }
 
 std::string DartLibraryProviderFiles::CanonicalizePackageURL(std::string url) {
   DCHECK(StartsWithASCII(url, "package:", true));
   ReplaceFirstSubstringAfterOffset(&url, 0, "package:", "");
   return package_root_.Append(url).AsUTF8Unsafe();
 }
 
 Dart_Handle DartLibraryProviderFiles::CanonicalizeURL(Dart_Handle library,
                                                       Dart_Handle url) {
   std::string string = blink::StdStringFromDart(url);
   if (StartsWithASCII(string, "dart:", true))
     return url;
   if (StartsWithASCII(string, "package:", true))
     return blink::StdStringToDart(CanonicalizePackageURL(string));
   base::FilePath base_path(blink::StdStringFromDart(Dart_LibraryUrl(library)));
   base::FilePath resolved_path = base_path.DirName().Append(string);
   base::FilePath normalized_path = SimplifyPath(resolved_path);
   return blink::StdStringToDart(normalized_path.AsUTF8Unsafe());
 }
 
 }  // namespace shell
 }  // namespace sky