Add comments and fix a potential leak in LaunchProcess.

I found a need to look at the implementation to confirm that process_handle would never be assigned to if the call failed. So I added a comment for future readers.

While doing so, I found an edge case where I think the process handle could be leaked.

BUG=None
TEST=Ask a random developer whether they must check process_handle if LaunchProcess returns false. If they look at process_util_*.cc, fail.


Review URL: http://codereview.chromium.org/9689081

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@126890 0039d316-1c4b-4281-b951-d872f2087c98

• base/process_util.h[diff]
• base/process_util_win.cc[diff]