The recent change for setting LD_LIBRARY_PATH doesn't actually work, as the

      script is executed by /bin/sh. On many systems, /bin/sh does not have support
for &quot[[&quot. We could either switch to a different shell (e.g. /bin/bash), we
could switch to using &quot[&quot instead, or we could avoid the entire problem by
using &quot${:+}&quot variable expansion.

I tested that the latter does the right thing with /bin/bash, /bin/ash,
/bin/dash, /bin/zsh, /bin/sh (the latter being a symbolic link to /bin/dash).
So, I think we are on the safe side.

BUG=54132
TEST=Start Chrome and notice that there no longer is an error message about &quot[[&quot being unavailable
Review URL: http://codereview.chromium.org/3412004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@59579 0039d316-1c4b-4281-b951-d872f2087c98