[LinearProgress] Remove dead code

[szrharrison]

There is a class that is listed in the docs that is never used (bar2Determinate)

• This is not a v0.x issue.
• I have searched the issues of this repository and believe that this is not a duplicate.

Expected Behavior 🤔

There should not be an unused class listed in the docs.

Current Behavior 😯

A class is listed in the docs that does nothing

Steps to Reproduce 🕹

Your Environment 🌎

Tech	Version
Material-UI	v3.5.1
React	v16.6.3
Browser	any

[joshwooding]

It looks like it shouldn't be in the code at all since the second bar isn't used when the variant is determinate 😅

https://github.com/mui-org/material-ui/blob/28df11846c049ef0aac00edbc35fef40d8d80bd3/packages/material-ui/src/LinearProgress/LinearProgress.js#L227-L233

[oliviertassinari]

Oh great, it's dead code, we can remove
https://github.com/mui-org/material-ui/blob/28df11846c049ef0aac00edbc35fef40d8d80bd3/packages/material-ui/src/LinearProgress/LinearProgress.js#L102
and
https://github.com/mui-org/material-ui/blob/28df11846c049ef0aac00edbc35fef40d8d80bd3/packages/material-ui/src/LinearProgress/LinearProgress.js#L196
😄

[oliviertassinari]

@szrharrison Do you want to take care of it? :)

[ekoeditaa]

@oliviertassinari I can help with this if nobody is doing it

[oliviertassinari]

Sure :)