Allow merging of changes from one release to another, again.
Allow merging of changes from one release to another, again.

When I updated cros_merge_to_branch to start using our new APIs and
allow for multiple checkouts per project, I also accidentally made our
reference logic here too strict -- it only allows you to reference a
repository if the checkout branch is the same as the change branch. I've
loosened that requirement here, allowing merging of changes from one
release branch to another, again.

BUG=chromium:320895
TEST=cros_merge_to_branch 66664 R32

Change-Id: I6041b4dcaacf5d1f55ab703f6e1c5855c79922dc
Reviewed-on: https://chromium-review.googlesource.com/177461
Reviewed-by: David James <f231dc574bbeb62604660cbc162d1b8642a0a3af@chromium.org>
Tested-by: David James <f231dc574bbeb62604660cbc162d1b8642a0a3af@chromium.org>
Reviewed-by: Mike Frysinger <8f3f75c74bd5184edcfa6534cab3c13a00a2f794@chromium.org>
Commit-Queue: Mike Frysinger <8f3f75c74bd5184edcfa6534cab3c13a00a2f794@chromium.org>

bpsinc-native/src_third_party_chromite,chadversary/chromiumos.chromite,bpsinc-native/src_third_party_chromite,chadversary/chromiumos.chromite,bpsinc-native/src_third_party_chromite