fix(ng_show_hide): make NG_HIDE_CLASS const

[trinarytree]

[googlebot]

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[trinarytree]

I signed it!

On Tue, Jun 23, 2015 at 11:18 PM, googlebot notifications@github.com wrote:

Thanks for your pull request. It looks like this may be your first contribution to a Google open source project, in which case you'll need to sign a Contributor License Agreement (CLA).

[image: :memo:] Please visit https://cla.developers.google.com/ https://cla.developers.google.com/ to sign.

Once you've signed, please reply here (e.g. I signed it!) and we'll

verify. Thanks.

• If you've already signed a CLA, it's possible we don't have your GitHub username or you're using a different email address. Check your existing CLA data https://cla.developers.google.com/clas and verify that your email is set on your git commits https://help.github.com/articles/setting-your-email-in-git/.
• If you signed the CLA as a corporation, please let us know the company's name.

— Reply to this email directly or view it on GitHub https://github.com/angular/angular.dart/pull/1732#issuecomment-114743573 .

[googlebot]

CLAs look good, thanks!