Omit commit position for Blink lastchange / version

DEPS

 # This file is used to manage the dependencies of the Chromium src repo. It is
 # used by gclient to determine what version of each dependency to check out, and
 # where.
 #
 # For more information, please refer to the official documentation:
 #   https://sites.google.com/a/chromium.org/dev/developers/how-tos/get-the-code
 #
 # When adding a new dependency, please update the top-level .gitignore file
 # to list the dependency's destination directory.
 #
@@ skipping 574 matching lines @@
     'name': 'lastchange',
     'pattern': '.',
     'action': ['python', 'src/build/util/lastchange.py',
                '-o', 'src/build/util/LASTCHANGE'],
   },
   {
     # Update LASTCHANGE.blink.
     'name': 'lastchange',
     'pattern': '.',
     'action': ['python', 'src/build/util/lastchange.py',
+               '--git-hash-only',
                '-s', 'src/third_party/WebKit',
                '-o', 'src/build/util/LASTCHANGE.blink'],
   },
   {
     # Update CANARY_VERSION.
     'name': 'ios_canary_version',
     'pattern': '.',
     'action': ['python', 'src/ios/build/util/canary_version.py',
                '-o', 'src/ios/build/util/CANARY_VERSION'],
   },
@@ skipping 197 matching lines @@
     # migration completes (let's say Sep 1 2014).
     'name': 'check_git_config',
     'pattern': '.',
     'action': [
         'python',
         'src/tools/check_git_config.py',
         '--running-as-hook',
     ],
   },
 ]