Implement handling of arrow functions in the parser

src/flag-definitions.h

 // Copyright 2012 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.
 
 // This file defines all of the flags.  It is separated into different section,
 // for Debug, Release, Logging and Profiling, etc.  To add a new flag, find the
 // correct section, and use one of the DEFINE_ macros, without a trailing ';'.
 //
 // This include does not have a guard, because it is a template-style include,
 // which can be included multiple times in different modes.  It expects to have
@@ skipping 148 matching lines @@
 DEFINE_bool(harmony_proxies, false, "enable harmony proxies")
 DEFINE_bool(harmony_collections, false,
             "enable harmony collections (sets, maps)")
 DEFINE_bool(harmony_generators, false, "enable harmony generators")
 DEFINE_bool(harmony_iteration, false, "enable harmony iteration (for-of)")
 DEFINE_bool(harmony_numeric_literals, false,
             "enable harmony numeric literals (0o77, 0b11)")
 DEFINE_bool(harmony_strings, false, "enable harmony string")
 DEFINE_bool(harmony_arrays, false, "enable harmony arrays")
 DEFINE_bool(harmony_maths, false, "enable harmony math functions")
+DEFINE_bool(harmony_arrow_functions, false, "enable harmony arrow functions")
 DEFINE_bool(harmony, false, "enable all harmony features (except typeof)")
 
 DEFINE_implication(harmony, harmony_scoping)
 DEFINE_implication(harmony, harmony_modules)
 DEFINE_implication(harmony, harmony_proxies)
 DEFINE_implication(harmony, harmony_collections)
 DEFINE_implication(harmony, harmony_generators)
 DEFINE_implication(harmony, harmony_iteration)
 DEFINE_implication(harmony, harmony_numeric_literals)
 DEFINE_implication(harmony, harmony_strings)
 DEFINE_implication(harmony, harmony_arrays)
+DEFINE_implication(harmony, harmony_arrow_functions)
 DEFINE_implication(harmony_modules, harmony_scoping)
 
 DEFINE_implication(harmony, es_staging)
 DEFINE_implication(es_staging, harmony_maths)
 DEFINE_implication(es_staging, harmony_symbols)
 
 // Flags for experimental implementation features.
 DEFINE_bool(packed_arrays, true, "optimizes arrays that have no holes")
 DEFINE_bool(smi_only_arrays, true, "tracks arrays with only smi values")
 DEFINE_bool(compiled_keyed_dictionary_loads, true,
@@ skipping 702 matching lines @@
 #undef DEFINE_ALIAS_float
 #undef DEFINE_ALIAS_args
 
 #undef FLAG_MODE_DECLARE
 #undef FLAG_MODE_DEFINE
 #undef FLAG_MODE_DEFINE_DEFAULTS
 #undef FLAG_MODE_META
 #undef FLAG_MODE_DEFINE_IMPLICATIONS
 
 #undef COMMA