Move forward/backward should change the visible ordering in the combo box

[samreid]

@matthew-blackman @zepumph and @arouinfar and I committed a fix in phetsims/sun#814 that makes it so that "Move forward" and "Move Backward" correctly skip over invisible children. That should be cherry picked for phetsims/qa#872. There is only one commit to cherry-pick, it is phetsims/scenery@6fe6985. That SHA may change after we merge the branch to master (@zepumph thinks it won't though).

The same should be done for ph-scale-basics as part of phetsims/qa#873

[pixelzoom]

This blocks publication of the next RC. It needs to be patched into both ph-scale 1.6 and ph-scale-basics 1.6.

[pixelzoom]

Since #271 went so poorly due to migration problems, I'm waiting to move forward on this issue until all migration-related issues are resolved and patched.

[zepumph]

@samreid and I will cherry pick this.

[samreid]

This is cherry picked, and @zepumph and I verified it locally. It is straightforward to confirm and does not require QA expertise for verification. @zepumph and I will verify it again in RC.2.

[zepumph]

This looks great in the published RC version (basics too). Closing.

I tested:

• that invisible items in the combo box aren't noticed when using "move up" or "move down"
• You cannot move up or down past the edges
• When you move past an invisible node, and then display the visible node again, it is still in the correct location.