Fix pub batch files on Windows.

Fix pub batch files on Windows.

They should handle spaces in paths correctly now.

BUG=https://code.google.com/p/dart/issues/detail?id=10104
R=nweiz@google.com

Committed: https://code.google.com/p/dart/source/detail?r=31150

[nweiz, 2013-12-13 22:56:50]

I don't know Windows batch well enough to understand what this patch is doing.
Can you get a review from someone who does?

[Bob Nystrom, 2013-12-13 23:12:42]

On 2013/12/13 22:56:50, nweiz wrote:
> I don't know Windows batch well enough to understand what this patch is doing.
> Can you get a review from someone who does?

There are only four actual changes here:

1. The line-noisy bit that starts with "for". I copied that verbatim from the
dart2js batch file.
2. I rearranged the order of a couple of the variables for no good reason. They
are unchanged.
3. I removed a trailing "/" from package root. It made Dart not yell at me.
4. I quoted %PACKAGES_DIR% in the invocation. That fixes it to handle spaces in
the path.

[nweiz, 2013-12-13 23:16:26]

lgtm, although I'm not a big fan of cargo-culting the line noise line.

[Bob Nystrom, 2013-12-14 00:08:33]

On 2013/12/13 23:16:26, nweiz wrote:
> lgtm, although I'm not a big fan of cargo-culting the line noise line.

I don't think of it as cargo-culting. We've always tried to keep those batch
files in sync with each other. For some reason that change to the dart2js batch
file didn't make it to the pub ones.

- bob

[Bob Nystrom, 2013-12-14 00:09:31]

Committed patchset #1 manually as r31150 (presubmit successful).