transparent mesh rotated?

```
What steps will reproduce the problem?
1. Changing transparency of the loaded mesh seems rotates it a little bit.

- this an an original loaded file, it's opaque
https://drive.google.com/file/d/0B86_WY0vcTRkd0hzdi00eHFrVmc/view

- applied 10% transparency only and didnt' move the mesh at all
https://drive.google.com/file/d/0B86_WY0vcTRkcHU4RGFKRVhldkE/view

- started to rotate the transparent mesh
https://drive.google.com/file/d/0B86_WY0vcTRkQ2F2Y2d2TTVUcHc/view
https://drive.google.com/file/d/0B86_WY0vcTRkVG44UXdRaG01a2M/view

2.
3.

What is the expected output? What do you see instead?

What version of the product are you using? On what operating system?
the latest one from trunk, win/linux. chrome browser

Please provide any additional information below.
using webgl mode, doublesided mesh

```

Original issue reported on code.google.com by `vlvin...@gmail.com` on 11 Mar 2015 at 5:34

No file, test, or entry point is named. First reproduce the issue in WebGL mode with the linked opaque and transparent mesh examples on Chrome under Windows or Linux; done means changing transparency no longer rotates or moves the double-sided mesh.

Written by the indexing model from the issue text.