gn: Add chromium_builder_asan target.

chrome/chrome_syzygy.gyp

 # Copyright (c) 2011 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.
 {
   'variables': {
     'dest_dir': '<(PRODUCT_DIR)/syzygy',
   },
   'conditions': [
     ['syzyasan==1', {
       'variables': {
@@ skipping 23 matching lines @@
         },
       ],
     }],
     ['OS=="win" and fastbuild==0', {
       'conditions': [
         ['syzygy_optimize==1 or syzyasan==1', {
           'variables': {
             'dll_name': 'chrome',
           },
           'targets': [
+            # GN version: //chrome/tools/build/win/syzygy:chrome_dll_syzygy
             {
               'target_name': 'chrome_dll_syzygy',
               'type': 'none',
               'sources' : [],
               'includes': [
                 'chrome_syzygy.gypi',
               ],
             },
           ],
         }],
         ['chrome_multiple_dll==1', {
           'conditions': [
             ['syzyasan==1 or syzygy_optimize==1', {
               'variables': {
                 'dll_name': 'chrome_child',
               },
               'targets': [
+                # GN version: //chrome/tools/build/win/syzygy:chrome_child_dll_syzygy
                 {
                   'target_name': 'chrome_child_dll_syzygy',
                   'type': 'none',
                   # For the official SyzyASan builds just copy chrome_child.dll
                   # to the Syzygy directory.
                   'conditions': [
                     ['syzyasan==1 and buildtype=="Official"', {
                       'dependencies': [
                         'chrome_child_dll_syzygy_copy'
                       ],
@@ skipping 41 matching lines @@
                   },
                 ],
               }],
             }],
           ],
         }],
       ],
     }],
   ],
 }