Replace ToLower calls to the new format

components/mime_util/mime_util.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 "components/mime_util/mime_util.h"
 
 #include "base/containers/hash_tables.h"
 #include "base/lazy_instance.h"
 #include "base/strings/string_util.h"
 #include "build/build_config.h"
@@ skipping 133 matching lines @@
     unsupported_text_types_.insert(kUnsupportedTextTypes[i]);
   for (size_t i = 0; i < arraysize(kSupportedJavascriptTypes); ++i) {
     javascript_types_.insert(kSupportedJavascriptTypes[i]);
     non_image_types_.insert(kSupportedJavascriptTypes[i]);
   }
   for (size_t i = 0; i < arraysize(kSupportedCertificateTypes); ++i)
     non_image_types_.insert(kSupportedCertificateTypes[i].mime_type);
 }
 
 bool MimeUtil::IsSupportedImageMimeType(const std::string& mime_type) const {
-  return image_types_.find(base::StringToLowerASCII(mime_type)) !=
-         image_types_.end();
+  return image_types_.find(base::ToLowerASCII(mime_type)) != image_types_.end();
 }
 
 bool MimeUtil::IsSupportedNonImageMimeType(const std::string& mime_type) const {
   return non_image_types_.find(base::StringToLowerASCII(mime_type)) !=
              non_image_types_.end() ||
 #if !defined(OS_IOS)
          media::IsSupportedMediaMimeType(mime_type) ||
 #endif
          (base::StartsWith(mime_type, "text/",
                            base::CompareCase::INSENSITIVE_ASCII) &&
@@ skipping 60 matching lines @@
     if (base::EqualsCaseInsensitiveASCII(
             mime_type, kSupportedCertificateTypes[i].mime_type)) {
       return kSupportedCertificateTypes[i].cert_type;
     }
   }
 
   return net::CERTIFICATE_MIME_TYPE_UNKNOWN;
 }
 
 }  // namespace mime_util