How to reproduce:
1. Open the attached project "TestUIShader_trunk.zip"
2. Build And Run the project
3. Observe that circle in the middle of the screen is white
4. Close the Player
5. Close the Editor
6. Open "UnitySprites.cginc" in Editor/Data/CGIncludes
7. Add "c.g = 0; c.b = 0;" after line 88
8. Save the file
9. Repeat steps 1-2
Expected results: The circle is red
Actual results: The circle is white