[InputBase] Provide input adornments with FormControlContext

[mtidei]

• I have followed (at least) the PR section of the contributing guide.

Fixes #14360

[joshwooding]

Yeah... I was fairly certain this would break the variant inheriting 😅

[joshwooding]

@oliviertassinari Do we still need to set the value to null in InputBase if we do it in the InputAdornment?
https://github.com/mui-org/material-ui/blob/d939f2beadb05d33b8edc6d5cb4fa1b10c907ef8/packages/material-ui/src/InputBase/InputBase.js#L407

[eps1lon]

@oliviertassinari Do we still need to set the value to null in InputBase if we do it in the InputAdornment?

Comment got lost during #13590:
https://github.com/mui-org/material-ui/pull/13590/files#diff-1f94c95b4e8094138b96211b29be700eL180

Code got added in #10229:
https://github.com/mui-org/material-ui/pull/10229/files#diff-deaeb5c7e253bfa4f497fa8ace0b3607R237

Original change didn't include a test. To be safe we should add a test that would fail prior to #10229 and then see if this test would pass now without setting the value to null.

[joshwooding]

Original change didn't include a test. To be safe we should add a test that would fail prior to #10229 and then see if this test would pass now without setting the value to null.

I agree, we’ve asked @mtidei for help reproducing the error so we can add a test
#14360 (comment)