[iwyu] Include handles.h less.

src/i18n.h

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 // limitations under the License.
 
 #ifndef V8_I18N_H_
 #define V8_I18N_H_
 
-#include "src/handles.h"
 #include "src/objects.h"
 #include "unicode/uversion.h"
 
 namespace U_ICU_NAMESPACE {
 class BreakIterator;
 class Collator;
 class DecimalFormat;
 class SimpleDateFormat;
 }
 
 namespace v8 {
 namespace internal {
 
+template <typename T>
+class Handle;
+
 class DateFormat {
  public:
   // Create a formatter for the specificied locale and options. Returns the
   // resolved settings for the locale / options.
   static icu::SimpleDateFormat* InitializeDateTimeFormat(
       Isolate* isolate,
       Handle<String> locale,
       Handle<JSObject> options,
       Handle<JSObject> resolved);
 
@@ skipping 90 matching lines @@
   static const int kSize = kUnicodeString + kPointerSize;
 
  private:
   V8BreakIterator();
 };
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_I18N_H_