Convert remaining StringToLowerASCII to ToLowerASCII

mojo/shell/network_fetcher.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 "mojo/shell/network_fetcher.h"
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/files/file.h"
 #include "base/files/file_path.h"
@@ skipping 112 matching lines @@
   }
   if (!file.IsValid()) {
     LOG(ERROR) << "Error reading " << path.value();
     return false;
   }
   // The output is really a vector of unit8, we're cheating by using a string.
   std::string output(crypto::kSHA256Length, 0);
   ctx->Finish(string_as_array(&output), output.size());
   output = base::HexEncode(output.c_str(), output.size());
   // Using lowercase for compatiblity with sha256sum output.
-  *digest_string = base::StringToLowerASCII(output);
+  *digest_string = base::ToLowerASCII(output);
   return true;
 }
 
 bool NetworkFetcher::RenameToAppId(const GURL& url,
                                    const base::FilePath& old_path,
                                    base::FilePath* new_path) {
   std::string app_id;
   if (!ComputeAppId(old_path, &app_id))
     return false;
 
@@ skipping 105 matching lines @@
     loader_callback_.Run(nullptr);
     return;
   }
 
   response_ = response.Pass();
   loader_callback_.Run(owner.Pass());
 }
 
 }  // namespace shell
 }  // namespace mojo