Use %B format instead of %s\n\n%b to get the raw commit message from a hash.

\n doesn't work on Windows, and %B is shorter anyway.

BUG=586344

Review URL: https://codereview.chromium.org/1705193003

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@298845 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/git_cl.py b/git_cl.py
index 92c6cce..3023213 100755
--- a/git_cl.py
+++ b/git_cl.py
@@ -2021,7 +2021,7 @@
   if options.squash:
     # Try to get the message from a previous upload.
     shadow_branch = 'refs/heads/git_cl_uploads/' + cl.GetBranch()
-    message = RunGitSilent(['show', '--format=%s\n\n%b', '-s', shadow_branch])
+    message = RunGitSilent(['show', '--format=%B', '-s', shadow_branch])
     if not message:
       if not options.force:
         change_desc.prompt()