[iwyu] Include handles.h less.

src/conversions.h

 // Copyright 2011 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.
 
 #ifndef V8_CONVERSIONS_H_
 #define V8_CONVERSIONS_H_
 
 #include <limits>
 
 #include "src/base/logging.h"
-#include "src/handles.h"
 #include "src/utils.h"
 
 namespace v8 {
 namespace internal {
 
+template <typename T>
+class Handle;
 class UnicodeCache;
 
 // Maximum number of significant digits in decimal representation.
 // The longest possible double in decimal representation is
 // (2^53 - 1) * 2 ^ -1074 that is (2 ^ 53 - 1) * 5 ^ 1074 / 10 ^ 1074
 // (768 digits). If we parse a number whose first digits are equal to a
 // mean of 2 adjacent doubles (that could have up to 769 digits) the result
 // must be rounded to the bigger one unless the tail consists of zeros, so
 // we don't need to preserve all the digits.
 const int kMaxSignificantDigits = 772;
@@ skipping 161 matching lines @@
 // Converts a number into size_t.
 inline size_t NumberToSize(Object* number);
 
 // returns DoubleToString(StringToDouble(string)) == string
 bool IsSpecialIndex(UnicodeCache* unicode_cache, String* string);
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_CONVERSIONS_H_