Upgrade gsutil to 3.4

Upgrade gsutil to 3.4

This appears to fix a Windows download bug I'm hitting on the win perf bot.

Committed: https://code.google.com/p/dart/source/detail?r=6914

[Emily Fortuna, 2012-04-23 22:16:10]

I'm assuming the directory "20110627" indicates what revision of gsutil we're
running? Do we want to continue that convention? if not, do we really want
"gsutil/gsutil" directory structure?

Otherwise, lgtm

On 2012/04/23 21:56:09, vsm wrote:

[vsm, 2012-04-24 21:52:47]

I'm collapsing the two directories as suggested and landing.  Thanks!

On 2012/04/23 22:16:10, Emily Fortuna wrote:
> I'm assuming the directory "20110627" indicates what revision of gsutil we're
> running? Do we want to continue that convention? if not, do we really want
> "gsutil/gsutil" directory structure?
> 
> Otherwise, lgtm
> 
> On 2012/04/23 21:56:09, vsm wrote: