Extend the constructColor function to handle 6 digit hex codes

[practual]

Description

When providing the TextTrackDisplay component with track settings overrides, currently colour codes with only three digits are supported. I would like to make this more flexible by also allowing six digit hex codes.

CC @arski

Specific Changes proposed

Updates the TextTrackDisplay component's constructColor function to accept and process both three and six digit colour codes.

Requirements Checklist

• Feature implemented / Bug fixed
• If necessary, more likely in a feature request than a bug fix
  • Change has been verified in an actual browser (Chome, Firefox, IE)
  • Unit Tests updated or fixed
  • Docs/guides updated
  • Example created (starter template on JSBin)
• Reviewed by Two Core Contributors

[arski]

nice, thanks. @gkatsev could you take a look please if you could include this

[OwenEdwards]

I'd like to see unit tests on this, to verify that both color formats work. I've got some work coming up in this same area, and I'd need to merge it with this change, so I'd want to make sure that I didn't break anything in the merge.

[practual]

@OwenEdwards tests added.

[misteroneill]

LGTM, thanks for this!

[gkatsev]

Other than the rest of the code base not using switches, this looks good to me.

[OwenEdwards]

@gkatsev is there a downside to switchs, rather than if...else...?

[gkatsev]

You definitely have to be more careful with switches due to their auto fall through and default case.

[gkatsev]

Also, it doesn't match the rest of our code :)

[practual]

I find switch statements cleaner than a lot of else ifs for the same variable, but will change it if you want.

[practual]

@gkatsev ping.

[gkatsev]

I think I would prefer it to be if statements over a switch for consistency.

[practual]

@gkatsev updated.

[gkatsev]

Thanks @practual