V8 Buildbot: Add mac64 asan trybot.

scripts/slave/recipes/v8.expected/full_tryserver_v8_v8_mac64_asan_rel.json

 [
   {
     "cmd": [
       "python",
       "-u",
       "[BUILD]/scripts/slave/bot_update.py",
       "--master",
       "tryserver.v8",
       "--builder",
-      "v8_linux64_asan_rel",
+      "v8_mac64_asan_rel",
       "--slave",
       "TestSlavename",
       "--spec",
       "cache_dir = None\nsolutions = [{'custom_vars': {'chromium_trunk': 'svn://svn-mirror.golo.chromium.org/chrome/trunk'}, 'deps_file': 'DEPS', 'managed': True, 'name': 'v8', 'url': 'https://chromium.googlesource.com/v8/v8'}]",
       "--root",
       "v8",
       "--revision_mapping_file",
       "{\"v8\": \"got_revision\"}",
       "--patch_url",
       "svn://svn-mirror.golo.chromium.org/patch",
@@ skipping 32 matching lines @@
   },
   {
     "cmd": [
       "python",
       "-u",
       "[DEPOT_TOOLS]/gclient.py",
       "runhooks"
     ],
     "cwd": "[SLAVE_BUILD]",
     "env": {
-      "GYP_DEFINES": "asan=1 clang=1 dcheck_always_on=0 fastbuild=1 gomadir='[BUILD]/goma' lsan=1 target_arch=x64 use_goma=1 v8_target_arch=x64",
+      "GYP_DEFINES": "asan=1 clang=1 dcheck_always_on=0 fastbuild=0 gomadir='[BUILD]/goma' lsan=1 target_arch=x64 use_goma=1 v8_target_arch=x64",
       "GYP_GENERATORS": "ninja"
     },
     "name": "gclient runhooks"
   },
   {
     "cmd": [
       "python",
       "-u",
       "[BUILD]/scripts/slave/cleanup_temp.py"
     ],
@@ skipping 122 matching lines @@
       "@@@STEP_LOG_LINE@durations@Command: d8 -f mjsunit/Cool.Test@@@",
       "@@@STEP_LOG_LINE@durations@Duration: 01:01:002@@@",
       "@@@STEP_LOG_LINE@durations@Test: mjsunit/Cool.Test2@@@",
       "@@@STEP_LOG_LINE@durations@Flags: -f -g@@@",
       "@@@STEP_LOG_LINE@durations@Command: d8 -f mjsunit/Cool.Test2@@@",
       "@@@STEP_LOG_LINE@durations@Duration: 00:00:101@@@",
       "@@@STEP_LOG_END@durations@@@"
     ]
   }
 ]