fix: restore loader object in postcss config context

[kisenka]

ℹ️ Describe the big picture of your changes here to communicate to the maintainers
why we should accept this pull request. If it fixes a bug or resolves a feature
request, be sure to link to that issue.

Type

---

ℹ️ What types of changes does your code introduce?

Put an x in the boxes that apply

• Fix
• Perf
• Docs
• Test
• Chore
• Feature
• Refactor

SemVer

---

ℹ️ What changes to the current semver range does your PR introduce?

Put an x in the boxes that apply

• Bug (:label: Patch)
• Feature (:label: Minor)
• Breaking Change (:label: Major)

Issues

---

ℹ️ What issue (if any) are closed by your PR?

Replace #1 with the error number that applies

• Fixes #354

Checklist

---

ℹ️ You can also fill these out after creating the PR. If you're unsure about any of them, don't hesitate to ask. This is a reminder of what we are going to look for before merging your code.

Put an x in the boxes that apply.

• [] Lint and unit tests pass with my changes
• I have added tests that prove my fix is effective/works
• I have added necessary documentation (if appropriate)
• Any dependent changes are merged and published in downstream modules

[coveralls]

Coverage increased (+1.3%) to 89.308% when pulling 53a0005 on kisenka:loader-in-ctx into ce2adca on postcss:master.

[alexander-akait]

👍

[alexander-akait]

@kisenka will be great if you add test

[alexander-akait]

👍

[kisenka]

@michael-ciniawsky could you please take a look, thanks!

[kisenka]

@evilebottnawi @michael-ciniawsky could someone please merge and publish a new version?

[alexander-akait]

/cc @ai looks @michael-ciniawsky unavaliable, i can't merge without second eye and can't have right on publish

[ai]

Looks good. But I prefer to wait @michael-ciniawsky. I will release only critical issue.

@kisenka you can use GitHub version of postcss-loader before this PR will released.

[alexander-akait]

@ai looks like regression, in 1 version we have this feature https://github.com/postcss/postcss-loader/blob/v1.0.0/index.js#L72. For someone, this can be critical

[ai]

OK. I will release it today

[ai]

Released 👍