Remove use_allocator=none where it's implied.

scripts/slave/recipe_modules/chromium/config.py

 # Copyright 2013 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.
 
 import pipes
 
 from slave.recipe_config import config_item_context, ConfigGroup
 from slave.recipe_config import Dict, List, Single, Static, Set, BadConf
 from slave.recipe_config_types import Path
 
@@ skipping 378 matching lines @@
 def official(c):
   c.gyp_env.GYP_DEFINES['branding'] = 'Chrome'
   c.gyp_env.GYP_DEFINES['buildtype'] = 'Official'
   c.compile_py.mode = 'official'
 
 @config_ctx(deps=['compiler'])
 def asan(c):
   if 'clang' not in c.compile_py.compiler:  # pragma: no cover
     raise BadConf('asan requires clang')
   c.runtests.swarming_tags |= {'asan:1'}
-  if c.TARGET_PLATFORM == 'linux':
-    c.gyp_env.GYP_DEFINES['use_allocator'] = 'none'
   if c.TARGET_PLATFORM in ['mac', 'win']:
     # Set fastbuild=0 and prevent other configs from changing it.
     fastbuild(c, invert=True, optional=False)
 
   c.gyp_env.GYP_DEFINES['asan'] = 1
   c.gyp_env.GYP_DEFINES['lsan'] = 1
 
 @config_ctx(deps=['compiler'])
 def lsan(c):
   c.runtests.enable_lsan = True
@@ skipping 367 matching lines @@
     c.compile_py.goma_dir = None
     c.gyp_env.GYP_DEFINES['use_goma'] = 0
 
 @config_ctx()
 def chromium_deterministic_build(c):
   c.gyp_env.GYP_DEFINES['dont_embed_build_metadata'] = 1
 
 @config_ctx(includes=['chromium_clang'])
 def cast_linux(c):
   c.gyp_env.GYP_DEFINES['chromecast'] = 1