Small improvements to push-to-trunk.sh and merge-to-branch.sh.

Small improvements to push-to-trunk.sh and merge-to-branch.sh.

1.) When a back-merged patch applied at an offset, ignore the "Hunk #1 succeeded at ..." lines instead of printing a scary warning.
2.) When push-to-trunk was not called with "-c /path/to/chrome/src", explicitly ask for the path to help discoverability of the feature.
3.) Correctly convert "BUG=chromium:123
" to "(Chromium issue 123)" in the pre-made ChangeLog entry.

Committed: https://code.google.com/p/v8/source/detail?r=11321

[Jakob Kummerow, 2012-04-13 15:34:19]

Once more, these changes are untested :-)
But they're neither scary nor dangerous. Please take a look.

[danno, 2012-04-13 15:56:00]

lgtm