Add yangguo@chromium.org to src/snapshot/OWNERS and WATCHLISTS

WATCHLISTS

 # Copyright 2013 the V8 project authors. All rights reserved.
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 #       notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 #       copyright notice, this list of conditions and the following
 #       disclaimer in the documentation and/or other materials provided
@@ skipping 18 matching lines @@
 # Refer: http://dev.chromium.org/developers/contributing-code/watchlists
 
 # IMPORTANT: The regular expression filepath is tested against each path using
 # re.search, so it is not usually necessary to add .*.
 
 {
   'WATCHLIST_DEFINITIONS': {
     'public_api': {
       'filepath': 'include/',
     },
+    'snapshot': {
+      'filepath': 'src/snapshot/',
+    },
+    'debugger': {
+      'filepath': 'src/debug\.(cc|h)|src/.*-debugger\.js|src/runtime/runtime-debug\.cc',
+    },
   },
 
   'WATCHLISTS': {
     'public_api': [
       'phajdan.jr@chromium.org',
     ],
+    'snapshot': [
+      'yangguo@chromium.org',
+    ],
+    'debugger': [
+      'yangguo@chromium.org',
+    ],
   },
 }