[libchromeos] Update to compile against revved libchrome

A header or two has moved around; update paths.  Also, remove
some conflicting (and unneeded) forward declarations.

Lastly, the logging in ProcessImpl::Wait() didn't correctly extract
the signal number that killed a process, in the event that the process
failed to exit normally.  This seems to have been working OK by
happenstance.  This adds the appropriate macro to extract the signal
number in all cases.

BUG=chromium-os:38805
TEST=build libchromeos and run unittests.

Change-Id: If2fe14b869cf5a7d569d2b927fe612df7ffbd567
Reviewed-on: https://gerrit.chromium.org/gerrit/43103
Tested-by: Chris Masone <cmasone@chromium.org>
Reviewed-by: Mike Frysinger <vapier@chromium.org>
Commit-Queue: Chris Masone <cmasone@chromium.org>
5 files changed