Make sure files end with exactly one new line and police this in presubmit.

Make sure files end with exactly one new line and police this in presubmit.

The changes are (excluding presubmit.py) mechanical. I added the following
lines after the check and iterated the presubmit script until all errors
went away:

f = open(name, "w");
if contents.endswith('\n\n'):
  f.write(contents[0:-1])
else:
  f.write(contents + '\n')

R=jkummerow@chromium.org

Committed: https://code.google.com/p/v8/source/detail?r=18017

[Jakob Kummerow, 2013-11-22 13:47:07]

LGTM (reviewed presubmit.py and a handful of random samples, rubberstamped the
rest).

[Yang, 2013-11-22 13:53:43]

Committed patchset #2 manually as r18017 (presubmit successful).