When using git-rebase-update, pass --no-verify to git commit.

Otherwise this creates a mess for WIP branches that do not pass the git
pre-commit hook.

R=iannucci@chromium.org
BUG=

Review URL: https://codereview.chromium.org/1179273003

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@295742 0039d316-1c4b-4281-b951-d872f2087c98

git_common.py

@@ -656,7 +656,7 @@ def squash_current_branch(header=None, merge_base=None):
     # nothing to commit at this point.
     print 'Nothing to commit; squashed branch is empty'
     return False
-  run('commit', '-a', '-F', '-', indata=log_msg)
+  run('commit', '--no-verify', '-a', '-F', '-', indata=log_msg)
   return True