Stop prepending "r" to commit hashes in merge_to_branch.py

Stop prepending "r" to commit hashes in merge_to_branch.py

R=machenbach@chromium.org

Committed: https://crrev.com/e5dbfd06c3dab5934e846c40af2a8b7fb5cdf0d6
Cr-Commit-Position: refs/heads/master@{#30483}

[Michael Achenbach, 2015-08-31 11:54:08]

lgtm - note that this string is just used for printing in the end. It makes no
functional difference.

[adamk, 2015-08-31 17:23:22]

On 2015/08/31 11:54:08, Michael Achenbach wrote:
> lgtm - note that this string is just used for printing in the end. It makes no
> functional difference.

Yup, I understand. I noticed when I copied and pasted the commits to double
check with git show.

[adamk, 2015-08-31 17:23:29]

The CQ bit was checked by adamk@chromium.org

[commit-bot: I haz the power, 2015-08-31 17:23:41]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1298973007/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1298973007/1

[commit-bot: I haz the power, 2015-08-31 17:46:17]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-08-31 17:46:41]

Patchset 1 (id:??) landed as
https://crrev.com/e5dbfd06c3dab5934e846c40af2a8b7fb5cdf0d6
Cr-Commit-Position: refs/heads/master@{#30483}

[Michael Hablich, 2015-09-01 11:10:53]

A revert of this CL (patchset #1 id:1) has been created in
https://codereview.chromium.org/1321343002/ by hablich@chromium.org.

The reason for reverting is: Result when using the script: 

tools/release/merge_to_branch.py 
  File "tools/release/merge_to_branch.py", line 108
    self["revision_list"] = ", ".join(self["full_revision_list"]))
                                                                 ^
SyntaxError: invalid syntax
.

[adamk, 2015-09-01 15:50:22]

lgtm, thanks for the fix (and sorry for the breakage). Python is just not my
thing...