bin/sync-and-gyp: pass --deps='...' to `gclient sync`.

bin/sync-and-gyp

 #!/usr/bin/env python
 
 # Copyright 2015 Google Inc.
 #
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 # This script will update Skia's dependencies as necessary and run
 # gyp if needed.
 
 # Depends on: Python, Git, and depot_tools.
 #
 # Example usage:
 #
 #   git clone https://chromium.googlesource.com/chromium/tools/depot_tools.git
 #   export PATH="${PWD}/depot_tools:${PATH}"
 #   git clone https://skia.googlesource.com/skia
 #   cd skia
 #   python bin/sync-and-gyp
 #   ninja -C out/Debug && out/Debug/dm
 #
 # Once changes are made to DEPS or gyp/ or the source, call:
 #
 #   python bin/sync-and-gyp
 
+# To retreive and use all optional deps:
+#
+#   python bin/sync-and-gyp --deps=all
+#   ninja -C out/Debug && out/Debug/dm
+
 import fnmatch
 import hashlib
+import os
 import subprocess
-import os
 import sys
 
 skia_dir = os.path.join(os.path.dirname(__file__), os.pardir)
 
+skia_opt_deps = [arg for arg in sys.argv[1:] if arg.startswith('--deps=')]
+
 skia_out = os.environ.get("SKIA_OUT")
 if skia_out:
   skia_out = os.path.abspath(skia_out)
   hash_path = os.path.join(skia_out, 'gyp_hash')
 else:
   hash_path = os.path.join('out', 'gyp_hash')
 
 os.chdir(skia_dir)
 
 if not os.path.isfile('DEPS'):
   sys.stderr.write('DEPS file missing')
   exit(1)
 
 deps_hasher = hashlib.sha1()
 with open('DEPS', 'r') as f:
   deps_hasher.update(f.read())
+deps_hasher.update(repr(skia_opt_deps))
 deps_hash = deps_hasher.hexdigest()
 current_deps_hash = None
 if os.path.isfile('.deps_sha1'):
   with open('.deps_sha1', 'r') as f:
     current_deps_hash = f.read().strip()
 
 default_gclient_config = '''
 solutions = [
   { "name"        : ".",
     "url"         : "https://skia.googlesource.com/skia.git",
     "deps_file"   : "DEPS",
     "managed"     : False,
     "custom_deps" : {
     },
     "safesync_url": "",
   },
 ]
 cache_dir = None
 '''
 if current_deps_hash != deps_hash:
   # `gclient sync` is very slow, so skip whenever we can.
   if not os.path.isfile('.gclient'):
     with open('.gclient', 'w') as o:
       o.write(default_gclient_config)
+  gclient_sync_command = ['gclient', 'sync'] + skia_opt_deps
   try:
-    subprocess.check_call(['gclient', 'sync'])
+    sys.stdout.write('%r\n' % gclient_sync_command)
+    subprocess.check_call(gclient_sync_command)
   except:
     sys.stderr.write('\n`gclient sync` failed.\n')
     os.remove('.deps_sha1')  # Unknown state.
     exit(1)
   # Only write hash after a successful sync.
   with open('.deps_sha1', 'w') as o:
     o.write(deps_hash)
 
 hasher = hashlib.sha1()
 
@@ skipping 29 matching lines @@
       return f.read()
   return ''
 
 if cat_if_exists(hash_path).strip() != gyp_hash:
   env = os.environ.copy()
   if skia_out:
     env['SKIA_OUT'] = skia_out
   subprocess.call(['python', './gyp_skia'], env=env)
   with open(hash_path, 'w') as o:
     o.write(gyp_hash)